Appendix A: $8 Field link and sequence number

Subfield $8 contains data that identifies linked fields and may also propose a sequence for the linked fields. Subfield $8 may be repeated to link a field to more than one other group of fields. The structure and syntax for the field link and sequence number subfield is:

$8[linking number].[sequence number]\[field link type]

The linking number is the first data element in the subfield and required if the subfield is used. It is a variable-length whole number that occurs in subfield $8 in all fields that are to be linked. Fields with the same linking number are considered linked.

The sequence number is separated from the linking number by a period ( . ) and may be optional. It is a variable-length whole number that may be used to indicate the relative order for display of the linked fields (lower sequence numbers displaying before higher ones). If it is used it must occur in all $8 subfields containing the same linking number.

The field link type is separated from preceding data by a reverse slash ( \ ). It is a code indicating the reason for the link and it follows the link number or sequence number if present. In the absence of a field link type, it is assumed that subfield $8 is used for linking and sequencing 85X, 86X, or 87X fields (captions, enumeration and chronology, textual holdings, and/or item information). Subfield $8 is essential to link and order these fields.

The following one-character field link type codes have been defined in MARC for use in subfield $8:

a - Action

Code a is used in a record to link one or more fields with another field to which the processing or reference actions relate. This code is typically used only when there is more than one 5XX that relates to another 5XX field.

Example:

541 ## $81.1\a$3Public School and College Authority and Trade School and Junior College Authority project files$aFinance Dept.$cTransferred

583 ## $81.2\a$aAppraised$c198712-$ktjb/prr

583 ## $81.3\a$aScheduled$c19880127$ksrc/prr

583 ## $81.4\a$aArranged$c19900619$kmc/dmj

583 ## $81.5\a$aProcessed level 2$b90.160$c19901218$kmc/dmj

p - Metadata provenance

Code p is used in a record to link a field with another field containing information about provenance of the metadata recorded in the linked field.

u - General linking, type unspecified

Code u is used in cases when a specific link type is not appropriate. Code u may serve as a default value when there is no information about the reason for the link available.

x - General sequencing

Code x is used in a record to make a link between fields to show a sequence between them. The sequence could be one that orders the pieces of a long field that has been broken up, indicates the relative importance of fields within the sequence, or is used for some other sequencing purpose. Use of the sequence number in $8 is required when this code is used.

Note that subfield $8 is defined differently in field 852 where it is used to sequence related holdings records. See the description of field 852, subfield $8 for more information.

Examples:

583 ## $81.2$aExhibit$c1982/12/01 through 1982/03/01$jMuseum of Fine Arts

876 ## $81.2$aXAX1222-1$pA1234567

853 03 $81$aBd.$i(year)

853 03 $82$an.F:Bd$i(year)

863 30 $81.1$a1-21$i1911-1923/1924

863 30 $82.1$a1-25$i1925/1926-1942/1943

[Linking numbers 1 and 2 link each 853 field to its associated 863 field.]

853 00 $81$ano.$i(year)$j(month)

863 40 $81.1$a180-226$i1976-1981

863 44 $81.2$a228

863 40 $81.3$a230$i1982$jApr.

863 40 $81.4$a235$i1982$jDec.

863 40 $81.5$a237$i1983$jMar.

863 40 $81.6$a239-242$i1983$jJune-Oct.

[Incremented decimal sequence numbers added to the linking number in multiple 863 fields associated with a single field 853 (when the display captions are constant) assist in appropriate sequencing of the 863 fields.]

853 20 $81$av.$bno.$u12$vr$i(year)$j(month)

863 40 $81.1$a108$b1-6$i1989$j1-6

863 40 $81.2$a108$b7-12$i1989$j7-12

863 40 $81.3$a109$b1-6$i1990$j1-6

863 40 $81.4$a109$b7-12$i1990$j7-12

876 ## $81.1$aAAA1000-1-1$pA1481283827

876 ## $81.2$aAAA1000-1-3$pA1481283831

876 ## $81.3$aAAA1000-1-2$jLost$pA1481283845

876 ## $81.4$aAAA1000-1-5$pA1481283863

[The whole link and sequence number links the item fields to the appropriate 863 field.]

Application for fields 866-868 (Textual Holdings):

Subfield $8 contains data that links related 853-868 holdings data fields. Only a linking number is used in the Textual Holdings fields to include whether the field is:

- the only holdings data field in the holdings statement or the only holdings data field to be used for display,

- an alternative display for one or more portions of the holdings data in 863-865 Enumeration and Chronology field(s) contained in the holdings statement, or

- a holdings data field in addition to the 863-865 Enumeration and Chronology field(s) contained in the holdings statement.

The linking number used in subfield $8 is determined by the following conditions:

Linking number is 0

Holdings are recorded only in a 866-868 Textual Holdings field. No 853-855 Captions and Pattern and 863-865 Enumeration and Chronology fields occur in the holdings statement.

Example:

867 31 $80$a"Teacher’s guide" pt. A-B

Holdings data are recorded in the linked 853-855 Captions and Pattern and 863-865 Enumeration and Chronology fields but the display form of the holdings is recorded in a Textual Holdings field.

Example:

853 20 $81$a[captions and pattern]

853 20 $82$a[captions and pattern]

853 20 $83$a[captions and pattern]

863 43 $81.1$a[enumeration and chronology]

863 43 $82.1$a[enumeration and chronology]

863 43 $82.2$a[enumeration and chronology]

863 43 $83.1$a[enumeration and chronology]

866 40 $80$a[textual holdings for display]

[No display is generated from any of the 853/863 fields. Field 866 replaces all of the 853/863 fields for display purposes.]

Linking number is the same as the linking number in the linked 853-855 and 863-865 fields

One or more portions of the holdings data recorded in the 853-855 Captions and Pattern and 863-865 Enumeration and Chronology fields is also recorded in an 866-868 Textual Holdings field to provide an alternative form for display purposes. The linking number in subfield $8 must match the linking number in subfield $8 of the linked 853-855/863-865 fields that the 866-868 field replaces. The content of a Textual Holdings field must replace all of the Enumeration and Chronology fields linked to a Captions and Pattern field.

If multiple Captions and Pattern/Enumeration Chronology fields that have consecutive linking numbers are to be replaced for display purposes by a single Textual Holdings field, subfield $8 may be repeated in Textual Holdings field to record the linking number of each of the Captions and Pattern/Enumeration and Chronology fields to be replaced.

Example:

855 20 $81$a[captions and pattern]

855 20 $82$a[captions and pattern]

855 20 $83$a[captions and pattern]

855 20 $84$a[captions and pattern]

865 43 $81.1$a[enumeration and chronology]

865 43 $82.1$a[enumeration and chronology]

865 43 $83.1$a[enumeration and chronology]

865 40 $84.1$a[enumeration and chronology]

868 40 $82$83$a[textual holdings for display]

[Field 868 replaces the 855/865 fields having linking numbers 2 and 3. No display is generated from those fields.]

Optionally, separate 866-868 Textual Holdings fields, each with one subfield $8, may be used instead of a single 866-868 field with multiple subfields $8.

Linking number is unique and sequences the holdings data with the enumeration and chronology of the 863-865 fields

When part of the holdings data is recorded in the 853-855 Captions and Pattern and 863-865 Enumeration and Chronology fields and part is recorded in the Textual Holdings fields, displays may be generated from both types of fields. This situation may occur when the holdings are extremely complex or the publication pattern varies greatly for only a certain period of time. A unique whole number is used as the linking number in the Textual Holdings field to sequence the field among the linking numbers used in the 853-855/863-865 fields according to the enumeration and chronology recorded in each field.

Example:

855 20 $81$a[captions and pattern]

855 20 $83$a[captions and pattern]

865 40 $81.1$a[enumeration and chronology]

865 40 $83.1$a[enumeration and chronology]

868 41 $82$a[textual holdings]

[The enumeration/chronology of the holdings recorded in field 868 falls between the fields with linking numbers 1 and 3. A display may be generated from all of the fields.]

Content designator history:

Subfield $8 - Field link and sequence number: In 2004, two new field link type codes were defined: a - Action and x - General sequencing.

p - Metadata provenance [new, 2012]

u - General linking, type unspecified [new, 2016]

To return:

Use the key.