Indicators
First Undefined; contains a blank (^)
0 Current call number [OBSOLETE]
1 Earlier call number [OBSOLETE]
Second
0 Assigned by NLC
1 Call number assigned by the contributing library [OBSOLETE]
4 Assigned by agency other than NLC
Subfield Codes
$a Classification number (NR)
$b Item number (NR)
$d Volumes/dates to which call number applies (NR)
$5 Institution to which field applies (R) See Control Subfields
$6 Linkage (NR) See Control Subfields
$8 Field link and sequence number (R) See Control Subfields