Classification
005 - Computer programming, programs & data
8,996
004 - Data processing & computer science
8,481
006 - Special computer methods
5,381
500 - Natural sciences & mathematics
4,925
040 - [Unassigned]
1,980
620 - Engineering & allied operations
1,938
621 - Applied physics
1,513
003 - Systems
1,221
519 - Probabilities & applied mathematics
1,074
658 - General management
1,068
331 - Labor economics
961
000 - Computer science, information & general works
844
518 - Numerical analysis
837
600 - Technology
758
384 - Communications; telecommunication
452
511 - General principles of mathematics
443
330 - Economics
363
745 - Decorative arts
326
025 - Library operations
322
510 - Mathematics
272
530 - Physics
270
515 - Analysis
252
629 - Other branches of engineering
244
512 - Algebra
240
570 - Life sciences; biology
224
610 - Medicine & health
204
300 - Social sciences
197
371 - Schools & their activities; special education
159
670 - Manufacturing
158
700 - The arts; fine & decorative arts
141
374 - Adult education
135
302 - Social interaction
118
338 - Production
101
001 - Knowledge
96
650 - Management & auxiliary services
92
333 - Economics of land & energy
90
160 - Logic
88
516 - Geometry
88
381 - Commerce
87
612 - Human physiology
72
370 - Education
65
380 - Commerce, communications & transportation
63
551 - Geology, hydrology & meteorology
62
410 - Linguistics
58
153 - Mental processes & intelligence
57
910 - Geography & travel
54
363 - Other social problems & services
53
794 - Indoor games of skill
50
140 - Specific philosophical schools
48
332 - Financial economics
48
more ...