Classification
333 - Economics of land & energy
865
658 - General management
809
304 - Factors affecting social behavior
598
621 - Applied physics
486
006 - Special computer methods
480
338 - Production
365
363 - Other social problems & services
332
577 - Ecology
325
630 - Agriculture & related technologies
320
551 - Geology, hydrology & meteorology
278
004 - Data processing & computer science
219
620 - Engineering & allied operations
219
005 - Computer programming, programs & data
215
670 - Manufacturing
207
628 - Sanitary & municipal engineering
196
910 - Geography & travel
168
660 - Chemical engineering
166
624 - Civil engineering
157
579 - Microorganisms, fungi & algae
132
003 - Systems
130
629 - Other branches of engineering
130
690 - Buildings
103
720 - Architecture
94
330 - Economics
89
610 - Medicine & health
79
631 - Techniques, equipment & materials
79
306 - Culture & institutions
73
550 - Earth sciences
71
696 - Utilities
69
616 - Diseases
68
174 - Occupational ethics
67
571 - Physiology & related subjects
67
634 - Orchards, fruits & forestry
67
307 - Communities
63
332 - Financial economics
55
371 - Schools & their activities; special education
51
320 - Political science
48
370 - Education
48
650 - Management & auxiliary services
46
570 - Life sciences; biology
42
613 - Personal health & safety
41
664 - Food technology
40
691 - Building materials
39
580 - Plants (Botany)
38
581 - Specific topics in natural history
38
327 - International relations
33
344 - Labor, social, education & cultural law
33
303 - Social processes
32
519 - Probabilities & applied mathematics
28
301 - Sociology & anthropology
26
more ...