Classification
620 - Engineering & allied operations
4,359
621 - Applied physics
3,146
531 - Classical mechanics; solid mechanics
1,185
600 - Technology
843
700 - The arts; fine & decorative arts
764
530 - Physics
729
629 - Other branches of engineering
658
333 - Economics of land & energy
620
900 - History & geography
504
000 - Computer science, information & general works
490
610 - Medicine & health
399
330 - Economics
305
363 - Other social problems & services
263
003 - Systems
258
624 - Civil engineering
251
500 - Natural sciences & mathematics
240
515 - Analysis
226
580 - Plants (Botany)
216
380 - Commerce, communications & transportation
201
670 - Manufacturing
198
519 - Probabilities & applied mathematics
185
320 - Political science
157
576 - Genetics & evolution
157
540 - Chemistry & allied sciences
154
690 - Buildings
148
140 - Specific philosophical schools
140
658 - General management
138
660 - Chemical engineering
124
340 - Law
106
414 - Phonology & phonetics
97
551 - Geology, hydrology & meteorology
94
541 - Physical chemistry
89
510 - Mathematics
85
006 - Special computer methods
76
384 - Communications; telecommunication
76
518 - Numerical analysis
74
536 - Heat
72
745 - Decorative arts
72
520 - Astronomy & allied sciences
67
630 - Agriculture & related technologies
60
720 - Architecture
59
547 - Organic chemistry
58
691 - Building materials
54
004 - Data processing & computer science
53
370 - Education
52
612 - Human physiology
48
304 - Factors affecting social behavior
45
331 - Labor economics
41
534 - Sound & related vibrations
40
615 - Pharmacology & therapeutics
40
more ...