Classification
330 - Economics
141
320 - Political science
113
005 - Computer programming, programs & data
45
006 - Special computer methods
43
300 - Social sciences
36
616 - Diseases
33
004 - Data processing & computer science
32
620 - Engineering & allied operations
31
530 - Physics
22
630 - Agriculture & related technologies
21
304 - Factors affecting social behavior
17
900 - History & geography
17
551 - Geology, hydrology & meteorology
16
333 - Economics of land & energy
15
519 - Probabilities & applied mathematics
15
520 - Astronomy & allied sciences
15
577 - Ecology
15
610 - Medicine & health
15
621 - Applied physics
15
040 - [Unassigned]
13
003 - Systems
12
306 - Culture & institutions
12
338 - Production
10
363 - Other social problems & services
10
658 - General management
10
340 - Law
9
510 - Mathematics
9
301 - Sociology & anthropology
8
331 - Labor economics
8
332 - Financial economics
8
550 - Earth sciences
8
572 - Biochemistry
8
580 - Plants (Botany)
8
910 - Geography & travel
8
001 - Knowledge
7
370 - Education
7
500 - Natural sciences & mathematics
7
515 - Analysis
7
600 - Technology
7
541 - Physical chemistry
6
617 - Surgery & related medical specialties
6
700 - The arts; fine & decorative arts
6
930 - History of ancient world to ca. 499
6
518 - Numerical analysis
5
629 - Other branches of engineering
5
820 - English & Old English literatures
5
305 - Social groups
4
307 - Communities
4
364 - Criminology
4
380 - Commerce, communications & transportation
4
more ...