Classification
320 - Political science
65
300 - Social sciences
47
340 - Law
38
330 - Economics
19
900 - History & geography
13
306 - Culture & institutions
12
650 - Management & auxiliary services
11
610 - Medicine & health
10
658 - General management
9
301 - Sociology & anthropology
7
305 - Social groups
7
370 - Education
6
620 - Engineering & allied operations
5
150 - Psychology
4
333 - Economics of land & energy
4
361 - Social problems & social welfare in general
4
302 - Social interaction
3
304 - Factors affecting social behavior
3
327 - International relations
3
344 - Labor, social, education & cultural law
3
400 - Language
3
510 - Mathematics
3
618 - Gynecology, obstetrics, pediatrics & geriatrics
3
700 - The arts; fine & decorative arts
3
001 - Knowledge
2
006 - Special computer methods
2
297 - Islam, Babism & Bahai Faith
2
331 - Labor economics
2
337 - International economics
2
338 - Production
2
343 - Military, tax, trade & industrial law
2
371 - Schools & their activities; special education
2
380 - Commerce, communications & transportation
2
540 - Chemistry & allied sciences
2
570 - Life sciences; biology
2
615 - Pharmacology & therapeutics
2
616 - Diseases
2
621 - Applied physics
2
629 - Other branches of engineering
2
670 - Manufacturing
2
780 - Music
2
830 - Literatures of Germanic languages
2
003 - Systems
1
004 - Data processing & computer science
1
005 - Computer programming, programs & data
1
158 - Applied psychology
1
174 - Occupational ethics
1
200 - Religion
1
322 - Relation of state to organized groups
1
332 - Financial economics
1
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