Classification
330 - Economics
1,881
320 - Political science
1,541
616 - Diseases
1,142
620 - Engineering & allied operations
879
300 - Social sciences
777
621 - Applied physics
752
551 - Geology, hydrology & meteorology
750
900 - History & geography
731
333 - Economics of land & energy
706
610 - Medicine & health
704
577 - Ecology
695
571 - Physiology & related subjects
656
501 - Philosophy & theory
563
001 - Knowledge
556
530 - Physics
554
340 - Law
546
006 - Special computer methods
510
520 - Astronomy & allied sciences
501
304 - Factors affecting social behavior
482
370 - Education
474
541 - Physical chemistry
395
820 - English & Old English literatures
384
580 - Plants (Botany)
381
142 - Critical philosophy
373
363 - Other social problems & services
332
004 - Data processing & computer science
328
523 - Specific celestial bodies & phenomena
321
301 - Sociology & anthropology
316
515 - Analysis
305
005 - Computer programming, programs & data
269
160 - Logic
258
170 - Ethics
243
306 - Culture & institutions
242
630 - Agriculture & related technologies
236
519 - Probabilities & applied mathematics
232
338 - Production
214
658 - General management
210
100 - Philosophy & psychology
207
003 - Systems
201
660 - Chemical engineering
201
570 - Life sciences; biology
194
617 - Surgery & related medical specialties
194
572 - Biochemistry
192
910 - Geography & travel
188
634 - Orchards, fruits & forestry
183
531 - Classical mechanics; solid mechanics
180
576 - Genetics & evolution
176
410 - Linguistics
162
624 - Civil engineering
159
500 - Natural sciences & mathematics
158
more ...