Library of Congress Subject Classification
| A | General Works | Main Level |
| B | Philosophy, Psychology, & Religion | Main Level |
| C | Auxiliary Sciences of History | Second Level |
| D | General & Old World History | Second Level |
| E | History of America | Second Level |
| F | History of the United States & British, Dutch, French & Latin America | Second Level |
| G | Geography, Anthropology, & Recreation | Second Level |
| H | Social Sciences | Second Level |
| J | Political Science | Second Level |
| K | Law | Second Level |
| L | Education | Second Level |
| M | Music | Second Level |
| N | Fine Arts | Second Level |
| P | Language & Literature | Lower Level |
| Q | Science | Lower Level |
| R | Medicine | Lower Level |
| S | Agriculture | Lower Level |
| T | Technology | Lower Level |
| U | Military Science | Lower Level |
| V | Naval Science | Lower Level |
| Z | Bibliography, Library Science, & General Information Resources | Main Level |