Classification
331 - Labor economics
1,290
005 - Computer programming, programs & data
1,269
330 - Economics
954
620 - Engineering & allied operations
622
000 - Computer science, information & general works
514
320 - Political science
456
600 - Technology
449
658 - General management
447
700 - The arts; fine & decorative arts
405
500 - Natural sciences & mathematics
329
900 - History & geography
312
333 - Economics of land & energy
303
530 - Physics
296
363 - Other social problems & services
272
621 - Applied physics
266
610 - Medicine & health
243
374 - Adult education
226
380 - Commerce, communications & transportation
206
004 - Data processing & computer science
200
515 - Analysis
186
539 - Modern physics
184
384 - Communications; telecommunication
154
338 - Production
148
364 - Criminology
133
519 - Probabilities & applied mathematics
120
340 - Law
113
300 - Social sciences
109
140 - Specific philosophical schools
99
370 - Education
93
006 - Special computer methods
91
150 - Psychology
84
551 - Geology, hydrology & meteorology
82
576 - Genetics & evolution
78
580 - Plants (Botany)
76
629 - Other branches of engineering
69
100 - Philosophy & psychology
58
302 - Social interaction
56
670 - Manufacturing
55
520 - Astronomy & allied sciences
53
371 - Schools & their activities; special education
45
541 - Physical chemistry
42
630 - Agriculture & related technologies
40
664 - Food technology
40
628 - Sanitary & municipal engineering
38
540 - Chemistry & allied sciences
37
616 - Diseases
36
381 - Commerce
34
660 - Chemical engineering
34
368 - Insurance
33
301 - Sociology & anthropology
32
more ...