| First Indicator | Second Indicator |
|---|---|
| Existence in LC collection # - No information provided 0 - Item is in LC 1 - Item is not in LC |
Source of call number 0 - Assigned by LC 4 - Assigned by agency other than LC |
| Subfield Codes | |
|---|---|
|
|
Classification or call number that is taken from Library of Congress Classification or LC Classification Additions and Changes. The brackets that customarily surround alternate class/call numbers are not carried in the MARC record; they may be generated based on the presence of repeated $a subfields.
Second indicator values distinguish between content actually assigned by the Library of Congress and content assigned by an organization other than LC.
Note that only subfield $u is locally defined. The entire field description is repeated here for ease of use of this document.
First Indicator - Existence in LC collection
Whether or not the item is contained in the LC collections.
Used for all call numbers assigned by agencies other than the Library of Congress.
| 050 | #4$aNB933.F44$bT6 | ||||||||
Item is in the LC collections under the call number given in the field.
Other agencies should use this value when transcribing from LC cataloging copy on which the call number is neither enclosed within brackets nor preceded by a Maltese cross.
| 050 | 00$aZ695.7$b.B37 1980 | ||||||||
Item is not in the LC collections, or that it is not shelved under that number.
Used by other agencies when transcribing from LC copy on which the call number appears in brackets or is preceded by a Maltese cross. Brackets that customarily surround call numbers for items not in LC are not carried in the MARC record; they may be generated for display.
| 050 | 10$aBJ1533.C4$bL49 | ||||||||
Second Indicator - Source of call number
Whether the source of the class/call number is the Library of Congress or another organization.
Used when an institution is transcribing from LC cataloging copy.
| 050 | 00$aJK609$b.M2 | ||||||||
$a - Classification number
Classification number portion of the call number. The source of the classification number is Library of Congress Classification and the LC Classification-Additions and Changes. Subfield $a is repeated to record an alternative class number. The alternate class number is recorded following the last subfield of the call number. If the alternate class number also includes an item number, the item number is included in the same subfield $a as the alternate class number; it is not separately subfielded.
| 050 | 00$aQC861.2$b.B36 | ||||||||
| 050 | 00$aZ695.7$b.B37 1980 | ||||||||
| 050 | 00$aZ7164.N3$bL34 no. 9$aZ7165.R42$aHC517.R42 | ||||||||
| 050 | 00$aRC951 | ||||||||
$b - Item number
Item number portion of the call number. An item number is the Cutter, date, term, etc. that is added to a classification number to distinguish an item from any other item assigned the same classification number.
Organizations that use the Cutter-Sanborn Three-Figure Author Table may conform to Library of Congress item number practice by applying Subject Cataloging Manual: Shelflisting conventions.
| 050 | 00$aJX1974.7$b.M5 | ||||||||
| 050 | 00$aZ673.L7$bY | ||||||||
| 050 | 10$aHF5726$b.B27 1980 | ||||||||
| 050 | 00$aE506.5 6th$bG | ||||||||
| 050 | 00$aE514.6 10th$b.T76 1905 [The above two call numbers are call numbers for regimental histories.] |
||||||||
$0 - Authority record control number or standard number
See description of this subfield in Appendix A: Control Subfields.
$1 - Real World Object URI
See description of this subfield in Appendix A: Control Subfields.
$3 - Materials specified
Part of the described material to which the field applies. The subfield is used with archival-type materials; its use is parallel with the use of subfield $3 in other fields.
$6 - Linkage
See description of this subfield in Appendix A: Control Subfields.
$8 - Field link and sequence number
See description of this subfield in Appendix A: Control Subfields.
LCCNs - When the call number field consists only of a class number (letters followed by numbers, possibly including a period and also a space), no subfield $b is used.
| 050 | 00$aQA37 | ||||||||
| 050 | 00$aE525.5 123d | ||||||||
General rule is that the item number part of the call number begins at the last capital letter in the call number or the period, if present, preceding it.
| 050 | 00$aHF5549.5.R44$bM35 | ||||||||
Exceptions to the general rule for item numbers:
If the call number is followed by only a date, with no Cutter number, the date is contained in subfield $b.
| 050 | 00$aE457.92$b1967 | ||||||||
If the call number is followed by volume numbering that includes uppercase letters, these letters are ignored in locating the last capital letter.
| 050 | 00$aJX1977$b.A2 St/ESA/35 | ||||||||
| 050 | 00$aHA1501$bA, Nr. 615 | ||||||||
| 050 | 00$aHD28$b.Y555 vol. 55 Suppl. | ||||||||
If the call number begins with CS71, subfield $b contains the date.
| 050 | 00$aCS71.C323$b1977 | ||||||||
If the call number is for a classification schedule (i.e., it is a call number beginning with Z696.U5), the class letter(s) for the particular classification and any following digit(s) are recorded in subfield $a (as part of the classification). Subfield $b contains the date.
| 050 | 00$aZ696.U5E3$b1958 | ||||||||
| 050 | 00$aZ696.U5H-HJ$b1981 | ||||||||
Abbreviations subser. and Suppl. are recorded in subfield $b, even when there is no item number.
Capitalization - Alphabetic characters in the classification number portion of the field are generally uppercase.
Spacing - Any spaces that are desired as part of the call number must be input.
| 050 | 00$aDK274.3 1968$b.K39 | ||||||||
| 050 | 00$aVM341$b.M9 vol. 48 | ||||||||
| 050 | 00$aCS71.C323$b1977 | ||||||||
Display Constant
| [ ... ] | [brackets] |
Brackets that customarily surround call numbers for items not in LC or alternate class/call numbers are not carried in the MARC record. They may be system generated as a display constant associated with the first indicator value 1 or additional $a subfields.
|
Content designated field:
|
|||||||||
| 050 | 10$aHF5726$b.B27 1980 | ||||||||
|
Display example: [HF5726.B27 1980]
|
|||||||||
Prior to the definition of code 4 in the second indicator position in 1982, the first indicator in the visual materials specifications was undefined. Visual materials records created prior to 1982 may contain a # meaning undefined in the first indicator position.
In the serials specifications, the use of the second indicator position to indicate the type of series was made obsolete in 1976. The values were: 0 (No series involved), 1 (Main series), 2 (Subseries), 3 (Sub-subseries).
Second indicator was defined in 1982. Prior to that change, 050 was an agency-assigned field and contained only call numbers assigned by the Library of Congress. LC records created before the definition of this indicator may contain a blank (#) meaning undefined in this position.