Classification
333 - Economics of land & energy
320 - Political science
500
330 - Economics
389
363 - Other social problems & services
258
610 - Medicine & health
133
600 - Technology
121
700 - The arts; fine & decorative arts
103
304 - Factors affecting social behavior
87
900 - History & geography
73
380 - Commerce, communications & transportation
71
000 - Computer science, information & general works
68
370 - Education
66
620 - Engineering & allied operations
65
630 - Agriculture & related technologies
55
551 - Geology, hydrology & meteorology
54
140 - Specific philosophical schools
52
340 - Law
49
300 - Social sciences
37
530 - Physics
33
581 - Specific topics in natural history
32
580 - Plants (Botany)
28
338 - Production
24
100 - Philosophy & psychology
19
200 - Religion
14
500 - Natural sciences & mathematics
14
576 - Genetics & evolution
14
720 - Architecture
14
336 - Public finance
13
361 - Social problems & social welfare in general
13
658 - General management
11
400 - Language
10
170 - Ethics
8
800 - Literature & rhetoric
8
301 - Sociology & anthropology
7
410 - Linguistics
6
297 - Islam, Babism & Bahai Faith
5
350 - Public administration & military science
5
540 - Chemistry & allied sciences
5
621 - Applied physics
5
302 - Social interaction
3
414 - Phonology & phonetics
3
296 - Judaism
2
360 - Social problems & services; associations
2
364 - Criminology
2
381 - Commerce
2
520 - Astronomy & allied sciences
2
550 - Earth sciences
2
657 - Accounting
2
770 - Photography, photographs & computer art
2
780 - Music
2
more ...