Classification
330 - Economics
284
333 - Economics of land & energy
267
320 - Political science
94
363 - Other social problems & services
65
581 - Specific topics in natural history
32
600 - Technology
27
700 - The arts; fine & decorative arts
27
900 - History & geography
25
380 - Commerce, communications & transportation
22
630 - Agriculture & related technologies
20
340 - Law
17
551 - Geology, hydrology & meteorology
17
100 - Philosophy & psychology
15
610 - Medicine & health
15
300 - Social sciences
14
620 - Engineering & allied operations
14
000 - Computer science, information & general works
12
370 - Education
11
140 - Specific philosophical schools
10
361 - Social problems & social welfare in general
9
338 - Production
8
170 - Ethics
7
576 - Genetics & evolution
7
301 - Sociology & anthropology
4
304 - Factors affecting social behavior
4
336 - Public finance
4
500 - Natural sciences & mathematics
4
658 - General management
4
800 - Literature & rhetoric
3
200 - Religion
2
350 - Public administration & military science
2
400 - Language
2
540 - Chemistry & allied sciences
2
580 - Plants (Botany)
2
297 - Islam, Babism & Bahai Faith
1
303 - Social processes
1
332 - Financial economics
1
337 - International economics
1
360 - Social problems & services; associations
1
410 - Linguistics
1
720 - Architecture
1
770 - Photography, photographs & computer art
1
780 - Music
1