022 INTERNATIONAL STANDARD SERIAL NUMBER (R)
Indicators First Level of international interest ^ Level of international interest not specified 0 Serial of international interest; full record registered with ISSN Network 1 Serial not of international interest; abbreviated record registered with ISSN Network Second Undefined; contains a blank (^)
Subfield Codes $a International Standard Serial Number (NR) $l ISSN-L (NR) $m Canceled ISSN-L (R) $y Incorrect ISSN (R) $z Canceled ISSN (R) $2 Source (NR) $6 Linkage (NR) $8 Field link and sequence number (R)