RDF Site Summary 1.0 Modules: PRISM

Authors

Tony Hammond, Timo Hannay, Ben Lund

Nature Publishing Group

Version

Latest Version: http://nurture.nature.com/rss/modules/mod_prism.html

Status

Proposed

This RSS 1.0 module has been reviewed by the IDEAlliance PRISM Working Group and reflects the current PRISM specification, version 1.2. It is intended that revised versions of this module will be published as the PRISM specification is upgraded.

This module allows RSS 1.0 newsfeeds to make use of the basic PRISM metadata vocabulary.

Rights

Copyright © 2003,2004 by the Authors.

Permission to use, copy, modify and distribute the RDF Site Summary 1.0 Specification and its accompanying documentation for any purpose and without fee is hereby granted in perpetuity, provided that the above copyright notice and this paragraph appear in all copies. The copyright holders make no representation about the suitability of the specification for any purpose. It is provided "as is" without expressed or implied warranty.

This copyright applies to the RDF Site Summary 1.0 Specification and accompanying documentation and does not extend to the RSS format itself.

Description

The Publishing Requirements for Industry Standard Metadata (PRISM) specification defines a standard for interoperable content description, interchange, and reuse in both traditional and electronic publishing contexts. PRISM recommends the use of certain existing standards, such as XML, RDF, the Dublin Core, and various ISO specifications for locations, languages, and date/time formats. Beyond those recommendations, it defines a small number of XML namespaces and controlled vocabularies of values, in order to meet the goals listed above.

The PRISM working group, a joint effort of representatives from publishers and vendors in an initiative organized under IDEAlliance, prepared the current PRISM specification, version 1.2 - Request for Comment. That specification is authoritative and should be consulted for reference purposes. The PRISM element descriptions reproduced here are provided purely for the reader's convenience. They indicate the content models for each element, but not the cardinalities (or allowed occurrences) for each element.

The PRISM RSS 1.0 module augments the RSS core and Dublin Core modules with channel- and item-level elements taken from the basic PRISM vocabulary.

Note that Dublin Core is a PRISM vocabulary and the usage of Dublin Core terms within a PRISM document is qualified. As an example, the dc:relation term is not recommended for use with PRISM. The user is referred to section 5.2 of the PRISM specification for further details as regards PRISM recommendations for use of Dublin Core elements.

Namespace Declarations

• xmlns:prism="http://prismstandard.org/namespaces/1.2/basic/"

Model

<channel>, <item>, <image>, and <textinput> Elements:

• <prism:byteCount>
• <prism:category>
• <prism:complianceProfile>
• <prism:copyright>
• <prism:corporateEntity>
• <prism:coverDate>
• <prism:coverDisplayDate>
• <prism:creationDate>
• <prism:distributor>
• <prism:edition>
• <prism:eIssn>
• <prism:embargoDate>
• <prism:endingPage>
• <prism:event>
• <prism:expirationDate>
• <prism:hasAlternative>
• <prism:hasCorrection>
• <prism:hasFormat>
• <prism:hasPart>
• <prism:hasPreviousVersion>
• <prism:hasTranslation>
• <prism:industry>
• <prism:isCorrectionOf>
• <prism:isFormatOf>
• <prism:isPartOf>
• <prism:isReferencedBy>
• <prism:isRequiredBy>
• <prism:issn>
• <prism:issueIdentifier>
• <prism:issueName>
• <prism:isTranslationOf>
• <prism:isVersionOf>
• <prism:location>
• <prism:modificationDate>
• <prism:number>
• <prism:objectTitle>
• <prism:organization>
• <prism:person>
• <prism:publicationDate>
• <prism:publicationName>
• <prism:receptionDate>
• <prism:references>
• <prism:requires>
• <prism:rightsAgent>
• <prism:section>
• <prism:startingPage>
• <prism:subsection1>
• <prism:subsection2>
• <prism:teaser>
• <prism:volume>
• <prism:wordCount>

This section lists each of the 48 elements used in the basic PRISM vocabulary together with a content model for that element. A definition and comments are also supplied for ready reference. For a definitive description of element usage, however, the reader should consult the PRISM specification, version 1.2 - Request for Comment.

Some of the content models used in this section provide content models that use parameter entity references. Those parameter entities and their meanings are:

• <prism:byteCount> ( #PCDATA )
  Size, in 8-bit bytes, of the resource.
  Comments
  • Typically, prism:byteCount is the size of a file. That might be used to display an estimate of download time to a user, to serve as a quick check on if a file was transmitted correctly between systems, etc. If the resource is compressed, such as a JPEG image, prism:byteCount gives its compressed size, which is much easier to obtain. Abbreviations, such as kB, MB, .. MUST NOT be used.
  
  
• <prism:category rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:category> ( #PCDATA )
  The nature or genre of a resource's intellectual content.
  Comments
  • Recommended practice for PRISM implementations is to reference values fromTable 17: Categories (intellectual genre) as URIs. Text values are allowed, so implementations MUST be capable of handling them, although interoperation with text values cannot be guaranteed.
  • See dc:type in the spec for an explanation of the relation between dc:type, dc:format, and prism:category.
  
  
• <prism:complianceProfile> ( #PCDATA )
  The PRISM specification compliance profile that the resource asserts that it adheres to.
  Comments
  • An optional element that permits content to assert that it adheres to PRISM compliance profiles "TWO" or "ONE." If the element is not present, consuming systems MAY treat the resource's compliance profile as unknown, or they MAY treat it as specified in a contractual, human-interpretable assertion - that is, "Our contract with this producer says that they are profile two compliant, so my consuming system will assume that it is." If the element is present and populated with values "TWO" or "ONE", consuming systems MUST assume that compliance is as asserted in the element. If the element is present and unpopulated or populated with a value other than as specified here, the behavior of the consuming system is undefined.
  
  
• <prism:copyright> ( #PCDATA )
  Copyright statement for the resource.
  Comments
  • Typically this field will contain the same copyright statement as in the printed magazine. The © character may be provided directly, or by the numeric character entity "&#169;". Use of the &copy; character entity is discouraged.
  
  
• <prism:corporateEntity> ( #PCDATA )
  The name(s) of organizational units related to the resource, either as the financial owner or group responsible for the resource, and at a lower hierarchical level than the corporate entity named in dc:publisher.
  Comments
  • PRISM is not a model for describing corporate organizational structure, but in cases where users need to record a relationship of the form(s) described above, prism:corporateEntity elements can be used.
  
  
• <prism:coverDate> ( %TimeSpecification; )
  Date on the cover of a magazine issue, suitable for storing into a database field with a "date" datatype.
  Comments
  • The cover date on a magazine indicates the last date the issue should be displayed for sale, NOT the publication date as commonly believed. The value of the date SHOULD be given in YYYY-MM-DD format.
  • See also prism:coverDisplayDate.
  
  
• <prism:coverDisplayDate> ( %TimeSpecification; )
  Date on the cover of a magazine issue, provided as a textual string.
  Comments
  • This field has the same meaning as the prism:coverDate element the last date an issue should be displayed for sale. However, many issues will not have a simple date which can be loaded into a database field of a "date" datatype. For example, "Spring, 2002". Such dates should be placed into this element.
  • For the convenience of applications which allow the user to search content within a specified range of dates, both the prism:coverDate and the prism:coverDisplayDate elements may be provided. In applications where the cover date is to be displayed to a user, this element SHOULD be used in preference to prism:coverDate. The prism:coverDate element SHOULD be used for the date comparisons.
  
  
• <prism:creationDate> ( %TimeSpecification; )
  Date (and potentially the time) the identified resource was first created.
  Comments
  • A publisher will not usually send this information to external parties, but will only use it in internal applications such as editorial workflow. The prism:coverDate element will be more commonly sent to others.
  • In common with the other date and time fields, recommended best practice is to use a date and time format from [W3D-datetime].
  
  
• <prism:distributor rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:distributor> ( #PCDATA )
  An identifier for the distributor of the resource.
  Comments
  • The organization or individual that most recently made the resource available, typically as part of a value-added service such as aggregation, syndication, or distribution. If the Publisher is the most recent distributor, omit this field.
  • Advanced practice is to use a URI for the distributor as a value for the rdf:resource attribute.
  
  
• <prism:edition> ( #PCDATA )
  An identifier for one of several alternate issues of a magazine or other resource.
  Comments
  • An issue of a magazine may be produced in multiple editions, with each edition providing content customized for a particular demographic or geographic group. Fortune, for example, is produced in a Domestic edition, a European edition, and an Asian edition. While much of the content overlaps, there is some content that is peculiar to each edition.
  
  
• <prism:eIssn> ( #PCDATA )
  ISSN for an electronic version of the issue in which the resource occurs.
  Comments
  • Permits publishers to include a second ISSN, identifying an electronic version of the issue in which the resource occurs, therefore e(lectronic)Issn. If used, prism:eIssn MUST contain the ISSN of the electronic version. See prism:issn.
  
  
• <prism:embargoDate> ( %TimeSpecification; )
  Earliest date (potentially including time) the resource may be used according to the rights agreement, or clause in the rights agreement.
  Comments
  • It is common practice to "embargo" information provide it to publishers in advance under an agreement that it will not be published until the embargo expires at some specific date and time. After that the information may be released to the outside world.
  • Note: This element was known as prism:releaseTime in previous versions of the PRISM specification.
  • prism:embargoDate is not a property of the resource as much as it is a property of the agreement under which the resource is provided. Therefore, this element must occur within the context of a dc:rights element.
  
  
• <prism:endingPage> ( #PCDATA )
  Identifies the last page number for the resource.
  Comments
  • For use in bibliographic citation of resources. This element, when used, MUST hold the last page number on which any part of the resource occurs, regardless of sequential breaks or skips in page numbering. It MUST NOT be used in conjunction with the prism:startingPage element to arrive at a page count, since the resource may be printed across a non-contiguous page range.
  
  
• <prism:event rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:event> ( #PCDATA )
  An event (social gathering, phenomenon, or more generally something that happened at a specifiable place and time) referred to in order to indicate a subject of the resource.
  Comments
  • If there is more than one event related to a resource, include a separate instance of prism:event for each event. The value may be a text string or an authority file reference.
  
  
• <prism:expirationDate> ( %TimeSpecification; )
  Latest date (potentially including time) that the resource may be used according to a rights agreement.
  Comments
  • Since prism:expirationDate is a property of a rights agreement, not of the resource itself, this element must appear in the context of a dc:rights element.
  • If it is important that the time NOT be interpreted as a local time, a time zone must be specified. As documented in [W3C-NOTE-datetime], , the "Z" character indicates Universal Coordinated Time (formerly known as Greenwich Mean Time). Other time zones are indicated by hour and minute displacements from UTC. For example, US Eastern Standard time is five hours behind UTC, so 8:00 AM EST on January 15, 2002 is written as 2002-01-15T08:00-05:00. That same instant could also be written as any of:
    
    2002-01-15T05:00-08:00 (5:00 AM Pacific Standard Time)
    2002-01-15T13:00Z (1:00 PM UTC)
    2002-01-15T14:00+01:00 (2:00 PM in Paris, France)
  
  
• <prism:hasAlternative rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasAlternative> ( #PCDATA )
  Identifies an alternative resource in case the current resource cannot be used (typically because of rights restrictions).
  Comments
  • Identifies another resource that can be substituted in place of the current resource. This provides a means for avoiding unsightly things like printing blank rectangles containing "No rights to reproduce this image".
  • Alternatives are not simply a reformatting of the original work, they are a separate intellectual work. To point to alternatives which are a different resolution, color space, file format, etc. see prism:hasFormat. For alternatives which are newer or older versions of the same intellectual work, see prism:hasVersion.
  
  
• <prism:hasCorrection rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasCorrection> ( #PCDATA )
  Identifies any known corrections to the current resource.
  Comments
  • The prism:hasCorrection element identifies the "correction block", not a corrected version of the current resource. Typically this will be added by a content aggregator, not the publisher. Corrected versions of the resource can be identified with the hasVersion element.
  
  
• <prism:hasFormat rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasFormat> ( #PCDATA )
  Identifies another resource, which is essentially the same intellectual content as the current resource, but presented in another file format, or after some mechanical transformation like a different resolution, different color depth, etc.
  Comments
  • The prism:hasFormat element points from the original resource, to the alternative version derived from it. In other words, the metadata of the original resource will contain the prism:hasFormat element. The prism:isFormatOf element is used to point in the other direction, from the alternative back to the original. If the "original" version cannot be determined, use prism:hasFormat for both directions of the relationship.
  • The element is repeated if there are multiple alternative formats for the resource.
  
  
• <prism:hasPart rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasPart> ( #PCDATA )
  The described resource includes the referenced resource either physically or logically.
  Comments
  • prism:hasPart allows the metadata for an article to identify images, sidebars, tables, graphs, maps, illustrations, etc. in the article which exist as separate, identifiable, resources. The metadata for those resources can then be fetched, based on the identifier for the included resource.
  • Recommended best practice is to describe photos, etc. as separate objects, rather than embedding their metadata in the metadata for an article, in order to ease their reuse and to simplify data maintenance when the resources are reused. Best practice is also to identify the resources with URIs, rather than human-readable text descriptions, in order to enable automated handling of the resource.
  • The element is repeated if there are multiple parts included in the current resource.
  
  
• <prism:hasPreviousVersion rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasPreviousVersion> ( #PCDATA )
  Identifies a previous version of the current resource.
  Comments
  • Changes in version imply substantive changes in intellectual content rather than differences in format. For changes in format, use the prism:hasFormat element. For the special case of versions known as corrections, use prism:hasCorrection to point from the current resource to correction blocks. Use prism:hasPreviousVersion to point from the corrected resource back to the earlier one.
  
  
• <prism:hasTranslation rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:hasTranslation> ( #PCDATA )
  The described resource has been translated into another language, and the referenced resource is that translation.
  Comments
  • Points from the original article to the translation(s), which must have a different identifier than the original resource. The language of the translated version can be determined by looking up the metadata for the translated version.
  • Recommended best practice is to identify the translated version with a URI.
  
  
• <prism:industry rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:industry> ( #PCDATA ) | <prism:industry> )
  An industry or industry sector, referred to in order to indicate a subject of the resource.
  Comments
  • If there is more than one industry related to a resource, include a separate instance of prism:industry for each industry. The value may be a text string or an authority file reference, or an authority file entry can be included inline.
  
  
• <prism:isCorrectionOf rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isCorrectionOf> ( #PCDATA )
  The described resource is a corrected version of the referenced resource.
  Comments
  • This element is a sub-property of the prism:isVersion element, and is the inverse of the prism:hasCorrection element.
  • The working group requests feedback on whether it is better to use prism:isCorrectionOf, or to use something like: <prism:category>correction</prism:category> <prism:hasPreviousVersion>id-for-the-earlier-version</prism:hasPreviousVersion>.
  
  
• <prism:isFormatOf rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isFormatOf> ( #PCDATA )
  The current resource is the same intellectual content of the referenced resource, but presented in another format.
  Comments
  • This is the inverse of the prism:hasFormat relation. It is used to point from the modified version to an earlier version. It is only used when it is known that the referenced resource is closer to being the "original" than the current resource.
  
  
• <prism:isPartOf rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isPartOf> ( #PCDATA )
  The described resource is a physical or logical part of the referenced resource.
  Comments
  • This is the inverse of the prism:hasPart relation. Note that it is NOT required to always have both sides of the relationship asserted, as one can be derived from the other.
  • Recommended best practice is to identify the containing resource with a URI. However, textual identifiers are possible so implementations SHOULD be able to accept them, possibly with reduced functionality.
  
  
• <prism:isReferencedBy rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isReferencedBy> ( #PCDATA )
  The described resource is referenced, cited, or otherwise pointed to by the referenced resource. [DCMI-R]
  Comments
  • This is the inverse of the prism:references relation.
  • [This seems a likely candidate for removal. The working group request feedback on whether this element must be kept.]
  
  
• <prism:isRequiredBy rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isRequiredBy> ( #PCDATA )
  The described resource is required by the referenced resource, either physically or logically.
  Comments
  • This is the inverse of the prism:requires relation.
  
  
• <prism:issn> ( #PCDATA )
  The ISSN for the publication in which the resource was published. If there are separate ISSNs for print and electronic versions, and if prism:issn is used, it MUST contain the ISSN for the print version. See prism:eIssn.
  
  
• <prism:issueIdentifier> ( #PCDATA )
  An additional identifier, typically used to record an identifier for a specific issue of a magazine or other resource, as distinct from the "special" name element, prism:issueName.
  Comments
  • This element provides an additional identifier, associating a resource with a periodical collection of resources - that is, an "issue" of a publication.
  
  
• <prism:issueName> ( %content.mix; )
  An additional identifier, typically used for major issues of a magazine or other resource.
  Comments
  • Certain issues of a magazine may be commonly known by a name like "Swimsuit issue" or "Buyer's Guide issue". These are frequently the issues which are the most memorable and have the material of greatest reference value. Issues may be tied to a particular day, but still be known by a name, such as the "Halloween issue". If an issue is known by a general date, such as "Spring, 2002", use the prism:coverDisplayDate element instead of this one.
  
  
• <prism:isTranslationOf rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isTranslationOf> ( #PCDATA )
  The described resource is a human-language translation of the referenced resource.
  Comments
  • This is a more specific version of prism:hasTranslation. This element is used when pointing from the translated resource back to the original. If the original resource is not known, the prism:hasTranslation element should be used for both directions of the relationship.
  • Best practice is to identify the original resource with a URI, but text identifiers are acceptable.
  
  
• <prism:isVersionOf rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:isVersionOf> ( #PCDATA )
  The described resource is a version, edition, or adaptation of the referenced resource.
  Comments
  • This is the inverse of prism:hasVersion. For corrections, use the subproperty prism:isCorrectionOf. For alternative versions that do not have substantive changes in intellectual content, use prism:isAlternativeFor.
  
  
• <prism:location rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:location> ( %content.mix; )
  A geospatial location, referred to in order to indicate a subject of the resource.
  Comments
  • As with other subject identifiers, the best practice is NOT to tag locations which are only mentioned in passing. The staff doing the tagging should assume that a full-text engine will be available to find those. The location element, on the other hand, is to call out those locations which are a subject for the story, no matter how many times they are mentioned in the story. As a test, the tagging staff should ask themselves "if I was searching for information on location X, would I want to get this story as one of the search results?" If so, then it should be tagged with that location, otherwise not.
  • If there is more than one location related to a resource, include a separate instance of prism:location for each. The value may be a string or an authority file reference. This element SHOULD be used in preference to the dc:coverage element for geospatial locations.
  
  
• <prism:modificationDate> ( %TimeSpecification; )
  Date and time the resource was last modified.
  Comments
  • Publishers will not usually send this information to external parties, but will use it for internal applications.
  
  
• <prism:number> ( #PCDATA )
  Indication of the magazine issue.
  Comments
  • This element is intended to be used in combination with the prism:volume element to specify the magazine issue using the common scheme of Volume and Number. The prism:number element must contain only a single identifier. In the case of a double issue a magazine with one volume number but two issue numbers the element is repeated, with each containing only a single number.
  
  
• <prism:objectTitle rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:objectTitle> ( %content.mix; )
  The name of a physical or virtual object, referred to in order to indicate a subject of the resource.
  Comments
  • This element is particularly intended for use when categorizing content by products, such as for product reviews. For example, <prism:objectTitle>Dodge Viper<prism:objectTitle> would be used to indicate that a subject of the story was a certain high-performance automobile.
  • If there is more than one object related to a resource, include a separate instance of prism:objectTitle for each. The value may be a string or an authority file reference.
  
  
• <prism:organization rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:organization> ( %content.mix; )
  An organization, referred to in order to indicate a subject of the resource.
  Comments
  • This element is used to indicate a company, government agency, non-profit organization, etc. as a subject of the current resource. If there is more than one organization related to a resource, include a separate instance of prism:organization for each. The value may be a text string or an authority file reference.
  
  
• <prism:person rdf:resource="%AuthorityReference;"> ( EMPTY ) | <prism:person> ( %content.mix; )
  A person, referred to in order to indicate a subject of the resource.
  Comments
  • Recommended best practice is to cite an entry into a controlled vocabulary of people. However, textual names are acceptable and are expected to be commonly used.
  • As with other subject identifiers, do not mark a resource for every person mentioned in the resource, only those which it is "about".
  • PRISM makes no recommendation on the issue of direct vs. sort order for names (in other words, we do not recommend "Smith, Jane Q." vs. "Jane Q. Smith").
  • If there is more than one person who is a subject of a resource, include a separate instance of prism:person for each.
  
  
• <prism:publicationDate> ( %TimeSpecification; )
  Announced date and time when the resource is released to the public.
  Comments
  • For magazines, this element will rarely be used. If it is used, the publication date for an issue is the date that it became available for sale. It is NOT the cover date. See prism:coverDate and prism:coverDisplayDate for that information.
  • For other resources, such as product reports published to a corporate web site, publicationDate is the day (and possibly time) the report was deployed to the live web site.
  • Recommended practice is to use the format from ISO 8601 (see section 4.4.1) including time zone data.
  
  
• <prism:publicationName> ( #PCDATA )
  Title of the magazine, or other publication, in which a resource was/will be published.
  Comments
  • Typically this will be used to provide the name of the magazine an article appeared in, as metadata for the article, along with information such as the article title, the publisher, volume, number, and cover date.
  
  
• <prism:receptionDate> ( %TimeSpecification; )
  Date (and potentially time) the resource was received on current system.
  Comments
  • This element will not usually be provided by a publisher. Instead, it is provided so aggregators can inform their customers of the time when the aggregator received the resource from the publisher.
  
  
• <prism:references rdf:resource="%ResourceReference;"> ( EMPTY ) | <prism:references> ( #PCDATA )
  The described resource references, cites, or otherwise points to the referenced resource.
  Comments
  • Use is to collect bibliography entries into metadata for the resource described. When multiple items are cited, use one prism:references element per item.
  
  
• <prism:requires rdf:resource="%ResourceReference;"> ( EMPTY )
  The described resource requires the referenced resource to support its function, delivery, or coherence of content.
  Comments
  • This is the inverse of the prism:isRequiredBy relation.
  
  
• <prism:rightsAgent> ( %content.mix; )
  Name, and possibly contact information, for the person or organization that should be contacted to license the rights to use a resource.
  Comments
  • This element should contain human-readable information. PRISM recommends that this be a simple text element. However, the content of this element may be elements from other namespaces, such as one that gives contact information, should such a namespace be acceptable to all the parties in the PRISM communication.
  
  
• <prism:section> ( #PCDATA )
  Name of the magazine section in which the resource was categorized. A section is a logical subdivision of a magazine which helps to identify the general subject domain of the contained content. It does NOT refer to the hierarchical organization of an article into sections and sub-sections. In general, sections are named, may contain one or more stories, and may be either recurring or one-time. Stories may or may not be associated with a section.
  Comments
  • Corresponds to magazine and newspaper sections. Sections without story content, such as "Table of Contents" and "Letters to the Editor" are also possible. Some sections will have subsections for example a section on 'Economy' might have subsections for Europe, Asia, the US, and Latin America. See the prism:subsection1 and prism:subsection2 elements for marking subsections and sub-subsections.
  • Note that some demographically-targeted editions may contain sections which are not available in the other editions of an issue.
  
  
• <prism:startingPage> ( #PCDATA )
  Identifies the first page number for the published version of the resource.
  Comments
  • Provided to meet the needs of basic bibliographic citation of articles. A more complete description of an article's pages is possible, but more difficult to obtain. Current practice is adequately addressed with a starting page number. People who want to look at the number of pages to get an estimate of the article's length should look at the prism:wordCount or prism:byteCount elements.
  
  
• <prism:subsection1> ( #PCDATA )
  Name of the subsection of the magazine in which the resource was printed. Also applies to other forms of publication, such such as websites. Should follow the prism:section element, and precede the prism:subsection2 element (if one is given).
  
  
• <prism:subsection2> ( #PCDATA )
  Name of the sub-subsection of the magazine in which the resource was printed. Also applies to other forms of publication, such as websites. Should follow the prism:subsection1 element.
  
  
• <prism:teaser> ( %content.mix; )
  A short description of the resource.
  Comments
  • This provides a place for short descriptions, such as those given in an issue's Table of Contents, or displayed in the results of an online search, which try to entice readers to read the full article.
  • The content of the prism:teaser element MUST be plain text, or text marked up with well-balanced XML content (in order to allow features such as bold or italicized text, URLs, etc. If the content contains XML markup, the rdf:parseType="Literal" attribute MUST be specified.
  
  
• <prism:volume> ( #PCDATA )
  Additional identifier for the publication where the resource appeared, providing the Volume portion of the common Volume, Number scheme.
  Comments
  • Provided for basic bibliographic citations. The content SHOULD NOT contain "Vol." Or other abbreviations for "Volume", it should only be the alphanumeric volume identifier. The Number portion of the issue identification is specified in the prism:number element.
  
  
• <prism:wordCount> ( #PCDATA )
  The (approximate) count of the number of words in a textual resource.
  Comments
  • PRISM does not mandate a specific word counting algorithm, as there are no known algorithms which are widely accepted for use across multiple languages. Therefore, the information provided by this field must be regarded as advisory. It can be displayed to a user to give an indication of the length of the article, but it can not be depended upon as a check on the correct transmission of a document.
  • The value is a single integer. Abbreviations such as 'k' MUST NOT be used.
  
  

Example

<?xml version="1.0" encoding="UTF-8"?>

<rdf:RDF
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