050 Library of Congress Call Number (R) (Variable Data Field)
Field 050 contains either a complete Library of Congress (LC) call number or an LC classification number assigned either by the Library of Congress or by other agencies using the Library of Congress Classification or LC Classification--Additions and Changes. The second indicator values distinguish between content actually assigned by the Library of Congress and content assigned by an organization other than LC.
The National level record requirement for this field is Optional.
Field 050 is repeatable .
Guidelines for applying content designators:
For indicator and subfield code definitions and examples, National-level (NLR) and Minimal-level (MLR) record requirements , and designator repeatability , see table below:
| Position | Description |
NLR |
MLR |
Repeatability |
| Field 050 | Library of Congress Call Number |
O |
O |
R |
| Indicator: | ||||
| First | Existence in LC collection |
M |
||
| # | No information provided |
A |
||
| 0 | Item is in LC |
A |
||
| 1 | Item is not in LC |
A |
||
| Second | Source of call number |
M |
||
| 0 | Assigned by LC |
A |
||
| 4 | Assigned by agency other than LC |
A |
||
| Subfield code: | ||||
| $a | Classification number |
M |
O |
R |
| $b | Item number |
A |
O |
NR |
| $3 | Materials specified |
O |
O |
NR |
| $6 | Linkage |
A |
O |
NR |
| $8 | Field link and sequence number |
O |
O |
R |
First Indicator - Existence in LC collection
Value # - No
information provided:
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 # (blank)
meaning undefined
in the first indicator position.
Second Indicator - Series
call number (SE)
[obsolete]: 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), and 3 (Sub-subseries).
Second Indicator - Source of call number
Value # - No
information provided
[obsolete]: The
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.
Subfield $d - Supplementary
class number (MU)
[obsolete, 1981]
Related MARC fields or documents:
Library of Congress Classification
LC Classification--Additions and Changes
Cutter-Sanborn Three-Figure Author Table
Subject Cataloging Manual: Shelflisting
LC Classification Outline, 6th Edition
See also:
