Classification
621 - Applied physics
1,172
333 - Economics of land & energy
725
600 - Technology
305
620 - Engineering & allied operations
293
330 - Economics
267
700 - The arts; fine & decorative arts
166
363 - Other social problems & services
154
000 - Computer science, information & general works
131
900 - History & geography
118
660 - Chemical engineering
84
338 - Production
75
380 - Commerce, communications & transportation
73
551 - Geology, hydrology & meteorology
64
580 - Plants (Botany)
58
629 - Other branches of engineering
56
320 - Political science
51
720 - Architecture
50
530 - Physics
48
304 - Factors affecting social behavior
40
658 - General management
40
610 - Medicine & health
34
541 - Physical chemistry
33
500 - Natural sciences & mathematics
32
628 - Sanitary & municipal engineering
30
576 - Genetics & evolution
28
630 - Agriculture & related technologies
28
006 - Special computer methods
26
140 - Specific philosophical schools
23
624 - Civil engineering
23
321 - Systems of governments & states
22
696 - Utilities
21
579 - Microorganisms, fungi & algae
20
540 - Chemistry & allied sciences
17
577 - Ecology
17
340 - Law
16
370 - Education
14
690 - Buildings
14
531 - Classical mechanics; solid mechanics
13
670 - Manufacturing
13
003 - Systems
11
800 - Literature & rhetoric
11
547 - Organic chemistry
9
581 - Specific topics in natural history
9
662 - Explosives, fuels & related products
8
910 - Geography & travel
8
004 - Data processing & computer science
7
550 - Earth sciences
7
572 - Biochemistry
7
300 - Social sciences
6
519 - Probabilities & applied mathematics
5
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