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Concise Formats - 2008 Archive >> Bibliographic >> 76X-78X

Linking Entry Fields (76X-78X)

This is an ARCHIVED VERSION of the 2008 electronic edition of the MARC 21 Concise Formats. Please see loc.gov/marc/concise/ for the most up-to-date version of the electronic MARC 21 Concise Formats.

Information that identifies other related bibliographic items. Each of the linking entry fields specifies a different relationship between the target item described by the record and a related item. These relationships fall into three classes: 1) related items that assist the user in continuing to search but are not physically required to obtain the target item (e.g., former entries for continuing resources, translations of the target item); 2) related items that have to be obtained physically in order to use the target item (e.g., the host item for a component part: a journal issue containing a specific article); 3) related items that are constituent units of a larger whole (e.g., the individual photographs contained in a visual material collection). The linking entry fields are designed to generate a note in a display of the record in which they appear. They can also provide machine linkage between the bibliographic record for the target item and the bibliographic record for the related item, if the related item is covered by a separate record; and/or facilitate indexing.

Definitions of terms used in the Linking Entry fileds:

Target Item - Bibliographic item that is the principal or primary unit covered by the description for which the record was constructed. The target item is the item to which the information in character positions 06 (Type of record) and 07 (Bibliographic level) of the Leader, and field 245 (Title Statement) apply.

Related Item - Bibliographic item that has a chronological, horizontal (different versions), or vertical (hierarchical) relationship with a target item, and for which the linking entry field is formulated.

Component Part - Bibliographic item that is physically part of another bibliographic item such that the retrieval of the part is dependent on the physical identification and location of the host item (e.g., a chapter in a book, an article in a journal). (Field 774)

Constituent Unit - Bibliographic item that is part of another item. The constituent unit is physically separate from the item of which it is considered a part. (Fields 770, 774)

Host Item - Bibliographic item that either physically contains (as in the case of the component part), or bibliographically includes (as in the case of a constituent unit), the subpart that is the target item for the record. For example, if a record describes a journal article, the host is the journal; if a record describes one digital item in a set, the host is the set. (Fields 772, 773)

Chronological Relationship - Relationship in time between bibliographic items (e.g., the relation of a serial to its predecessors and successors). (Fields 777, 780, 785)

Horizontal Relationship - Relationship between versions of a bibliographic item in different languages, formats, media, etc. (Fields 765, 767, 775, 776)

Vertical Relationship - Hierarchical relationship of the whole to its parts and the parts to the whole (e.g., a journal article to the journal, collective title of conference proceedings to individual titles of contributions, subseries to main entry series). (Fields 760, 762, 770)

RECORD LINKS AND NOTES

Linking Entry Fields (fields 760-787) - Fields carry descriptive data concerning the related item, the control number for the record of the related item, or both. Minimal content designation is provided for the data concerning the related item that is used in the linking entry fields. For data operations requiring fuller content designation such as indexing and sorting, subfield $w (control number for the related item) allows the system to follow that link to the related record to obtain fully content-designated data.

Moreover, the coded data in control subfield $7 allows some types of indexing without reference to the actual related record. The value used in the first indicator position of a linking entry field determines whether a note is to be generated from the the linking entry field or from field 580.

Linking Entry Complexity Note (field 580) - Linking Entry Fields are designed to support generation of a note concerning the related item in a display of the record for the target item. When the relationship is too complex to be expressed using a display constant and the data from the linking entry field or the linked record, the note is recorded in the Linking Entry Complexity Note field. When used, this field appears in addition to any relevant 760-787 linking entry field, and not note is generated from the linking entry field.

Added Entries (fields 700-730) - When an added entry is needed for a title used in a linking field, the added entry is recorded in the appropriate 700-730 field. Linking fields are not intended to take the place of added entries. Likewise, an added entry in field 700-730 does not take the place of a linking field, as it cannot cause a note to be generated or carry a record link.

Component Parts/Constituent Units - Linking entry field 773 (Host Item Entry) is used to link the record for a component part that is an integral part of another item to the record for the other item. For example, in records for journal articles, it contains an identification of the journal. The exact location of the article in the journal is recorded in subfield $g of field 773. The record for the host item or any larger bibliographic unit may include information about constituent units, recorded in the repeatable field 774 (Constituent Unit Entry). Information about each constituent would be recorded in a separate occurrence of field 774.