Classification
330 - Economics
1,471
551 - Geology, hydrology & meteorology
960
363 - Other social problems & services
521
333 - Economics of land & energy
381
700 - The arts; fine & decorative arts
256
000 - Computer science, information & general works
251
320 - Political science
208
600 - Technology
203
577 - Ecology
179
620 - Engineering & allied operations
156
580 - Plants (Botany)
135
900 - History & geography
132
630 - Agriculture & related technologies
127
581 - Specific topics in natural history
124
610 - Medicine & health
123
380 - Commerce, communications & transportation
118
140 - Specific philosophical schools
113
304 - Factors affecting social behavior
86
500 - Natural sciences & mathematics
61
338 - Production
59
576 - Genetics & evolution
57
300 - Social sciences
53
370 - Education
51
414 - Phonology & phonetics
42
340 - Law
39
658 - General management
39
720 - Architecture
38
100 - Philosophy & psychology
29
540 - Chemistry & allied sciences
28
550 - Earth sciences
26
800 - Literature & rhetoric
26
530 - Physics
23
170 - Ethics
18
344 - Labor, social, education & cultural law
18
612 - Human physiology
16
200 - Religion
14
621 - Applied physics
12
628 - Sanitary & municipal engineering
12
660 - Chemical engineering
12
910 - Geography & travel
12
400 - Language
9
301 - Sociology & anthropology
8
361 - Social problems & social welfare in general
8
631 - Techniques, equipment & materials
7
305 - Social groups
6
350 - Public administration & military science
6
571 - Physiology & related subjects
6
590 - Animals (Zoology)
6
360 - Social problems & services; associations
5
634 - Orchards, fruits & forestry
5
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