Mapping of Dublin Core Elements
to Z39.50 Bib-1 Search Attributes

Ray Denenberg and Rebecca Guenther, Library of Congress

Draft 2
July 22, 1997

Note: Draft 1 of this document was not widely circulated.
Following is a proposed mapping from Dublin Core elements to Z39.50 Bib-1 Search attributes. This mapping assumes, in general, non-qualified Dublin Core (with a few exceptions: Date, Coverage, and Language). As Dublin Core qualifiers become standardized, this mapping may be changed.

  1. Title
    Dublin Core element Title maps to bib-1 Use attribute title (4).

  2. Author/creator
    Dublin Core element Author/creator maps to bib-1 Use attribute Author (1003).

  3. Subject and Keywords
    Dublin Core element Subject and Keywords maps to bib-1 Use attribute Subject Heading (21).

  4. Description
    Dublin Core element Description maps to bib-1 Use attribute Abstract (62).

  5. Publisher
    Dublin Core element Publisher maps to bib-1 Use attribute publisher (1018).

  6. Other Contributors
    Dublin Core element Other Contributors maps to bib-1 Use attribute Author (1003).
    Discussion: Dublin Core element Other Contributors is intended to distinguish primary authors from secondary contributors, where the latter may include, for example, an illustrator. This distinction seems more meaningful for retrieval than for searching. Searching specifically on a secondary contributor seems unlikely; therefore Other Contributor maps to the same search access point as Author.
    This assumes, however, that Z39.50 servers will map Author both to primary and secondary authors. Field 720, Added entry - Uncontrolled Name (recently added to USMARC), should be added, in the Bib-1 set semantics, to the list of MARC fields corresponding to author (1003).

  7. Date
    Note: Dublin Core Workshop 4 concluded that the definition of element Date requires revision, to include various types of dates.
    Dublin Core element Date maps to one of the following bib-1 Use attributes, depending on the type of date to be searched: Additional Use attributes corresponding to additional date types will be proposed for addition to bib-1 if necessary.

  8. Resource Type
    Dublin Core element Resource Type maps to bib-1 Use attributes material type (1031) and content type (1034).

  9. Format
    Format will be proposed as new bib-1 Use attribute, corresponding to Dublin Core element Format.

  10. Resource Identifier
    Dublin Core element Resource Identifier maps to bib-1 Use attributes identifier--standard (1007), and doc-id (1032).
    Note: Identifier--standard would be used for ISBN, ISSN, etc., and doc-id for urls, etc. However, doc-id might not be appropriate based on its definition, from the bib-1 semantics document: "A persistent identifier, or Doc-ID, assigned by a server, that uniquely identifies a document on that server." The primary problem with this definition is the implication of persistence. But common usage of attribute doc-id does not seem to assume persistence, thus the definition may not be consistent with common usage, and a proposal may be developed to modify that definition.

  11. Source
    Source will be proposed as new bib-1 Use attribute, corresponding to Dublin Core element Source.

  12. Language
    Dublin Core element Language maps to bib-1 Use attribute code-language (54), for use when the supplied search term is a language code.
    An additional bib-1 Use attribute, text-language, will be proposed, for use when the search term is a language specified in text form (e.g. "english").

  13. Relation
    Dublin Core element Relation is currently regarded as an experimental element, requiring further development. Therefore a mapping to bib-1 is premature, and none is currently proposed.

  14. Coverage
    Dublin Core element Coverage maps to bib-1 Use attribute map-scale (1024) for spatial coverage. For temporal coverage, a new bib-1 Use attribute, temporal-coverage, will be proposed.

  15. Rights Management
    The content of Dublin Core element Rights Management might be an actual rights management statement, or it may be a link to a rights management statement. The requirement(s) for searching have not been articulated. However, the following requirements have been speculated: to search within a rights management statement (assuming that the content is an actual statement rather than a pointer); or to locate documents that point to a specific rights management statement, or documents that have or do not have a rights management pointer (assuming that the content is a pointer). Proposed mapping(s) are deferred pending clarification of search requirements (comments solicited). There may be a need to search within a statement and/or on a link. These would correspond to different bib-1 Use attributes: "rights management statement" and "rights management link". One or both of these may be proposed as new bib-1 attributes if necessary, as indicated by requirements.

Library of Congress
Comments July 22, 1997