Classification
620 - Engineering & allied operations
300 - Social sciences
65
600 - Technology
59
630 - Agriculture & related technologies
43
500 - Natural sciences & mathematics
36
330 - Economics
27
320 - Political science
24
900 - History & geography
24
363 - Other social problems & services
23
700 - The arts; fine & decorative arts
18
301 - Sociology & anthropology
16
333 - Economics of land & energy
16
370 - Education
14
303 - Social processes
13
100 - Philosophy & psychology
12
380 - Commerce, communications & transportation
11
000 - Computer science, information & general works
10
658 - General management
10
140 - Specific philosophical schools
9
384 - Communications; telecommunication
8
331 - Labor economics
7
340 - Law
7
400 - Language
6
720 - Architecture
6
780 - Music
6
170 - Ethics
5
364 - Criminology
5
610 - Medicine & health
5
745 - Decorative arts
5
006 - Special computer methods
4
302 - Social interaction
4
338 - Production
4
410 - Linguistics
4
540 - Chemistry & allied sciences
4
576 - Genetics & evolution
4
005 - Computer programming, programs & data
3
530 - Physics
3
551 - Geology, hydrology & meteorology
3
580 - Plants (Botany)
3
581 - Specific topics in natural history
3
025 - Library operations
2
200 - Religion
2
350 - Public administration & military science
2
360 - Social problems & services; associations
2
361 - Social problems & social welfare in general
2
362 - Social welfare problems & services
2
800 - Literature & rhetoric
2
120 - Epistemology, causation & humankind
1
155 - Differential & developmental psychology
1
304 - Factors affecting social behavior
1
more ...