| Subclass AC | Collections. Series. Collected works |
| Subclass AE | Encyclopedias |
| Subclass AG | Dictionaries and other general reference works |
| Subclass AI | Indexes |
| Subclass AM | Museums. Collectors and collecting |
| Subclass AN | Newspapers |
| Subclass AP | Periodicals |
| Subclass AS | Academies and learned societies |
| Subclass AY | Yearbooks. Almanacs. Directories |
| Subclass AZ | History of scholarship and learning. The humanities |
https://www.loc.gov/aba/cataloging/classification/lcco/lcco_a.pdf