050 LIBRARY OF CONGRESS CALL NUMBER (R)Indicators First Existence in LC collection ^ No information provided 0 Item is in LC 1 Item is not in LC Second Source of call number ^ No information provided [OBSOLETE] 0 Assigned by LC 4 Assigned by agency other than LCSubfield Codes $a Classification number (R) $b Item number (NR) $d Supplementary class number (MU) [OBSOLETE] $3 Materials specified (NR) $6 Linkage (NR) $8 Field link and sequence number (R)