 | A:
General Works |
| B-BD:
Philosophy |
| BF:
Psychology (also parapsychology and the occult) |
| BH-BJ:
Aesthetics, Ethics, Etiquette |
| BL-BX:
Religion
|
| C:
History: Auxiliary sciences |
| D:
History: General, and Regions Outside the Americas
 | DA
Great Britain and Ireland |
| DAW
Central Europe |
| DB
Austria, Hungary, Czech Republic, Slovakia |
| DC
France, Andorra, Monaco |
| DD
Germany |
| DE
Mediterreanean Region, Greco-Roman World |
| DF
Greece |
| DG
Italy |
| DH-DJ
Belgium, Luxembourg, Netherlands |
| DJK
Eastern Europe |
| DK
Russia, Former Soviet Republics, Poland |
| DL
Northern Europe, Scandinavia |
| DP
Spain, Portugal |
| DR
Balkan Region |
| DS
Asia |
| DT
Africa |
| DU
Oceania, Australia, New Zealand |
| DX
Roma (Gypsies) |
|
| E:
History: United States (General) |
| F:
History: United States (Regional), and the Americas |
| G:
Geography, Anthropology, Folklore, Recreation
|
| H:
Social Sciences
| HA:
Statistics |
| HB-HJ:
Economics and Business
|
| HM:
Sociology (General) |
| HN:
Social History, Problems, and Reform |
| HQ:
Family, Marriage, Sex and Gender |
| HS:
Societies and Clubs |
| HT:
Cities, Communities, Ethnicity |
| HV:
Social Service, Welfare, Criminology |
| HX:
Socialism, Communism, Utopias, Anarchism |
|
| J:
Political Science |
| K:
Law (see also J for some constitutional works) |
| L:
Education |
| M:
Music |
| N:
Fine Arts |
| P:
Language and Literature
|
| Q:
Science
|
| R:
Medicine |
| S:
Agriculture |
| T:
Technology
|
| U:
Military Science |
| V:
Naval Science |
| Z:
Bibliography and Library Science |
