Classification
363 - Other social problems & services
162
330 - Economics
86
610 - Medicine & health
75
551 - Geology, hydrology & meteorology
57
700 - The arts; fine & decorative arts
57
333 - Economics of land & energy
50
620 - Engineering & allied operations
41
000 - Computer science, information & general works
40
600 - Technology
39
628 - Sanitary & municipal engineering
35
380 - Commerce, communications & transportation
31
900 - History & geography
22
320 - Political science
19
140 - Specific philosophical schools
18
577 - Ecology
15
621 - Applied physics
14
580 - Plants (Botany)
13
550 - Earth sciences
12
660 - Chemical engineering
11
630 - Agriculture & related technologies
10
615 - Pharmacology & therapeutics
9
658 - General management
9
629 - Other branches of engineering
8
720 - Architecture
8
370 - Education
7
338 - Production
6
530 - Physics
6
576 - Genetics & evolution
6
340 - Law
5
540 - Chemistry & allied sciences
5
500 - Natural sciences & mathematics
4
519 - Probabilities & applied mathematics
4
665 - Industrial oils, fats, waxes & gases
4
690 - Buildings
4
344 - Labor, social, education & cultural law
3
526 - Mathematical geography
3
570 - Life sciences; biology
3
616 - Diseases
3
003 - Systems
2
100 - Philosophy & psychology
2
304 - Factors affecting social behavior
2
400 - Language
2
410 - Linguistics
2
414 - Phonology & phonetics
2
541 - Physical chemistry
2
546 - Inorganic chemistry
2
549 - Mineralogy
2
574 - [Unassigned]
2
581 - Specific topics in natural history
2
613 - Personal health & safety
2
more ...