Classification
330 - Economics
651
519 - Probabilities & applied mathematics
304
616 - Diseases
289
006 - Special computer methods
156
570 - Life sciences; biology
129
658 - General management
127
610 - Medicine & health
125
612 - Human physiology
123
571 - Physiology & related subjects
101
300 - Social sciences
97
530 - Physics
90
005 - Computer programming, programs & data
89
333 - Economics of land & energy
82
510 - Mathematics
77
500 - Natural sciences & mathematics
65
620 - Engineering & allied operations
61
004 - Data processing & computer science
57
572 - Biochemistry
57
000 - Computer science, information & general works
54
576 - Genetics & evolution
54
700 - The arts; fine & decorative arts
52
338 - Production
50
332 - Financial economics
45
501 - Philosophy & theory
45
621 - Applied physics
44
615 - Pharmacology & therapeutics
41
512 - Algebra
40
320 - Political science
38
511 - General principles of mathematics
38
900 - History & geography
38
363 - Other social problems & services
37
410 - Linguistics
37
100 - Philosophy & psychology
36
001 - Knowledge
35
520 - Astronomy & allied sciences
35
577 - Ecology
35
304 - Factors affecting social behavior
34
150 - Psychology
33
331 - Labor economics
30
617 - Surgery & related medical specialties
30
551 - Geology, hydrology & meteorology
29
302 - Social interaction
28
515 - Analysis
28
580 - Plants (Botany)
27
600 - Technology
25
400 - Language
23
153 - Mental processes & intelligence
22
140 - Specific philosophical schools
21
370 - Education
21
380 - Commerce, communications & transportation
20
more ...