Classification
610 - Medicine & health
330 - Economics
441
700 - The arts; fine & decorative arts
255
380 - Commerce, communications & transportation
161
370 - Education
145
100 - Philosophy & psychology
102
140 - Specific philosophical schools
102
363 - Other social problems & services
101
600 - Technology
88
900 - History & geography
70
000 - Computer science, information & general works
63
170 - Ethics
53
362 - Social welfare problems & services
52
616 - Diseases
45
361 - Social problems & social welfare in general
41
612 - Human physiology
40
340 - Law
39
580 - Plants (Botany)
37
576 - Genetics & evolution
33
620 - Engineering & allied operations
24
800 - Literature & rhetoric
20
333 - Economics of land & energy
18
320 - Political science
16
615 - Pharmacology & therapeutics
13
658 - General management
13
614 - Incidence & prevention of disease
11
613 - Personal health & safety
10
551 - Geology, hydrology & meteorology
9
200 - Religion
6
400 - Language
6
305 - Social groups
5
304 - Factors affecting social behavior
4
331 - Labor economics
3
338 - Production
3
618 - Gynecology, obstetrics, pediatrics & geriatrics
3
630 - Agriculture & related technologies
3
306 - Culture & institutions
2
353 - Specific fields of public administration
2
365 - Penal & related institutions
2
368 - Insurance
2
371 - Schools & their activities; special education
2
372 - Elementary education
2
629 - Other branches of engineering
2
657 - Accounting
2
001 - Knowledge
1
025 - Library operations
1
150 - Psychology
1
300 - Social sciences
1
301 - Sociology & anthropology
1
302 - Social interaction
1
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