Classification
330 - Economics
50
004 - Data processing & computer science
49
005 - Computer programming, programs & data
49
304 - Factors affecting social behavior
49
610 - Medicine & health
45
320 - Political science
33
333 - Economics of land & energy
24
600 - Technology
21
006 - Special computer methods
19
370 - Education
18
336 - Public finance
10
003 - Systems
9
617 - Surgery & related medical specialties
8
620 - Engineering & allied operations
8
900 - History & geography
8
340 - Law
7
363 - Other social problems & services
7
327 - International relations
6
338 - Production
6
616 - Diseases
6
700 - The arts; fine & decorative arts
6
380 - Commerce, communications & transportation
5
515 - Analysis
5
660 - Chemical engineering
5
140 - Specific philosophical schools
4
300 - Social sciences
4
306 - Culture & institutions
4
519 - Probabilities & applied mathematics
4
720 - Architecture
4
025 - Library operations
3
303 - Social processes
3
307 - Communities
3
331 - Labor economics
3
510 - Mathematics
3
577 - Ecology
3
612 - Human physiology
3
621 - Applied physics
3
780 - Music
3
791 - Public performances
3
302 - Social interaction
2
305 - Social groups
2
332 - Financial economics
2
355 - Military science
2
378 - Higher education
2
381 - Commerce
2
518 - Numerical analysis
2
572 - Biochemistry
2
624 - Civil engineering
2
628 - Sanitary & municipal engineering
2
629 - Other branches of engineering
2
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