017 COPYRIGHT OR LEGAL DEPOSIT NUMBER (R)Indicators First Undefined contains a blank (^) Second Display constant controller 8 No display constant generated ^ Abbreviated key titleSubfield Codes $a Copyright registration number (R) $b Source (agency assigning number) (NR) $d Date (NR) $2 Source (NR) $6 Linkage (NR) $8 Field link and sequence number (R)