Classification
900 - History & geography
600 - Technology
155
620 - Engineering & allied operations
153
700 - The arts; fine & decorative arts
141
333 - Economics of land & energy
113
330 - Economics
86
363 - Other social problems & services
82
380 - Commerce, communications & transportation
72
320 - Political science
64
140 - Specific philosophical schools
62
000 - Computer science, information & general works
61
720 - Architecture
57
551 - Geology, hydrology & meteorology
30
610 - Medicine & health
30
500 - Natural sciences & mathematics
22
370 - Education
21
580 - Plants (Botany)
21
340 - Law
20
576 - Genetics & evolution
20
300 - Social sciences
15
630 - Agriculture & related technologies
13
581 - Specific topics in natural history
12
658 - General management
11
800 - Literature & rhetoric
10
400 - Language
9
540 - Chemistry & allied sciences
9
100 - Philosophy & psychology
8
301 - Sociology & anthropology
6
530 - Physics
6
590 - Animals (Zoology)
6
414 - Phonology & phonetics
5
170 - Ethics
4
200 - Religion
4
304 - Factors affecting social behavior
4
770 - Photography, photographs & computer art
4
361 - Social problems & social welfare in general
3
410 - Linguistics
3
657 - Accounting
3
360 - Social problems & services; associations
2
780 - Music
2
336 - Public finance
1
339 - Macroeconomics & related topics
1
550 - Earth sciences
1
612 - Human physiology
1
940 - History of Europe
1