Classification
610 - Medicine & health
103
613 - Personal health & safety
98
616 - Diseases
54
330 - Economics
47
614 - Incidence & prevention of disease
46
658 - General management
37
620 - Engineering & allied operations
27
158 - Applied psychology
26
363 - Other social problems & services
26
333 - Economics of land & energy
19
700 - The arts; fine & decorative arts
19
006 - Special computer methods
14
600 - Technology
14
140 - Specific philosophical schools
13
615 - Pharmacology & therapeutics
13
621 - Applied physics
13
005 - Computer programming, programs & data
12
004 - Data processing & computer science
10
100 - Philosophy & psychology
10
300 - Social sciences
10
331 - Labor economics
10
670 - Manufacturing
10
000 - Computer science, information & general works
9
338 - Production
9
370 - Education
9
500 - Natural sciences & mathematics
9
150 - Psychology
7
380 - Commerce, communications & transportation
7
362 - Social welfare problems & services
6
900 - History & geography
6
170 - Ethics
5
320 - Political science
5
551 - Geology, hydrology & meteorology
5
630 - Agriculture & related technologies
5
340 - Law
4
353 - Specific fields of public administration
4
540 - Chemistry & allied sciences
4
571 - Physiology & related subjects
4
612 - Human physiology
4
660 - Chemical engineering
4
304 - Factors affecting social behavior
3
306 - Culture & institutions
3
541 - Physical chemistry
3
617 - Surgery & related medical specialties
3
061 - Organizations in North America
2
155 - Differential & developmental psychology
2
301 - Sociology & anthropology
2
302 - Social interaction
2
368 - Insurance
2
519 - Probabilities & applied mathematics
2
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