உலாவல் - அழைப்பு எண்
- A - General Works
- B - Philosophy, Psychology, Religion
- C - Historical Sciences
- D - World History
- E - United States History
- F - General American History
- G - Geography, Anthropology, Recreation
- H - Social Science
- J - Political Science
- K - Law
- L - Education
- M - Music
- N - Fine Arts
- P - Language and Literature
- Q - Science
- R - Medicine
- S - Agriculture
- T - Technology
- U - Military Science
- Z - Library Science