| COMARC/A | October | 2022 |
The subfield indicates descriptive cataloguing rules or subject system, to which the access point belongs. The subfield is used, when the subject system differs from the system, entered in the field 152.
The subfield can be used in fields 4XX and 7XX.
The following code values are defined:
| bnf | Bibliothèque nationale de France (BNF) |
| gnd | Gemeinsame Normdatei (GND) |
| lc | Library of Congress Subject Headings (LCSH) |
| lcgft | Library of Congress Genre/Form Terms (LCGFT) |
| mesh | Medical Subject Headings (MeSH) |
| naf | Library of Congress/NACO Authority File (LC/NAF) |
| nsogi | Nuovo soggettario (NS) |
| ram | Répertoire d'autorité-matière encyclopédique et alphabétique unifié (RAMEAU) |
| sears | Sears List of Subject Headings (Sears) |
| sgce | COBISS.SI General List of Subject Headings |