Relation

Input guidelines:

General guidelines.

• The relation element indicates whether the resource currently being described has a formal or informal relationship to another resource.
• Use the relation element only where necessary for discovery, or if necessary to utilize the resource once identified. If possible, prefer Note to describe important relationships or requirements.
• It may be unnecessary to enter a relation element when two resources are already connected on the record by the same collection name, subject heading, etc. Consider whether the user is likely to find the related resource if the relation element is not present.
• As a rule of thumb, do not search for related resources as this would make cataloging time too extensive. Use the Relation element when in the course of cataloging, the cataloger becomes aware of related resources that may be of interest to the user.

Formulating the relation element.

• For the sake of interoperability, consistent relationships (qualifiers) should be used in formulating the relation element:
  • Is part of / has part
    Use for chapters, sections, etc. of a larger resource; use for collections.
  • Is version of / has version 
    Use for editions of a work.
  • Is format of / has format
    Use for a dataset transformed into an image, a file migrated from or to a new format, etc.
  • Is based on / is basis for
    Use for a translation of a work, a screenplay based on a book, etc.
  • Is required by  / requires
    Use when the described resource requires the referenced resource either physically or logically.
  • References / is referenced by
    Use to connect resources accompanying the main resource, or to refer to resources described or referenced in the main resource.
• Recommended best practice is to identify the related resource by a unique identifier such as an OCLC number, ISBN number, or other identifer as outlined in the Identifier element.  Also give the title, format, or any other additional bibliographic information deemed necessary for the user to understand the related item. 
• If both resources connected by a relation element are in the Portal, enter relation information in both records.

Related element.

• To make observations about related subject matter in the intellectual content of another resource (for example, photographs of the same storm-damaged building taken from different viewpoints), use the Note element.

Examples:

Is part of / has part.

A part of a larger resource.
Relation:  This chapter is part of Aesop's fables (Oxford: Oxford University Press, 2002), ISBN 0192840509

A larger resource or collection with a definitive sub-part.
Relation:  This resource has part of the manuscript for the autobiography of James Smith.

Is version of / has version.

A different edition.
Relation:  This resource is a version of View camera technique by Leslie Stroebel (London: Focal Press, 1972), ISBN 0240448545

Is format of / has format.

A file migrated from one format type to another.
Relation:  This resource is a Word file of a document originally prepared in WordPerfect.

Is based on / is basis for.

Two related works are featured in this example.  A relation element is completed for each resource:

A work based on another work.
Relation:  This motion picture is based on the novel The nun's story by Kathryn Hulme (Boston:  Little, Brown, 1956), OCLC no. 285499

A work that is the basis for another work.
Relation:  This novel is the basis for the motion picture The nun's story (directed by Fred Zinneman, produced by Warner Brothers, 1958; videocassette recording, 1988, available from Warner Home Video), OCLC no. 17885645

Is required by / requires.

Two related works are featured in this example.  A relation element is completed for each resource:

A work required for another work to be used successfully.
Relation:  This translation tool is required by the kit available in the Portal at identifier Y0236.

A work requiring another work to be used successfully.
Relation:  Use of this kit requires the translation tool available in the Portal at identifier X0235.

References / is referenced by.

Two related works are featured in this example.  A relation element is completed for each resource:

For a work referencing an accompanying resource.
Relation:  Text references accompanying map available in the Portal at identifier Z225501.

For a work referenced by a resource it accompanies.
Relation:  Map is referenced by Denton and its environs (Denton:  Madeup Press, 1976), available in the Portal at identifier W225502.