Classification
330 - Economics
45
333 - Economics of land & energy
43
700 - The arts; fine & decorative arts
42
000 - Computer science, information & general works
40
600 - Technology
35
363 - Other social problems & services
33
900 - History & geography
29
620 - Engineering & allied operations
23
380 - Commerce, communications & transportation
22
551 - Geology, hydrology & meteorology
18
320 - Political science
15
610 - Medicine & health
15
140 - Specific philosophical schools
14
340 - Law
12
500 - Natural sciences & mathematics
11
630 - Agriculture & related technologies
10
576 - Genetics & evolution
9
580 - Plants (Botany)
9
410 - Linguistics
8
370 - Education
6
400 - Language
6
720 - Architecture
6
800 - Literature & rhetoric
6
170 - Ethics
5
300 - Social sciences
5
658 - General management
4
414 - Phonology & phonetics
3
530 - Physics
3
612 - Human physiology
3
100 - Philosophy & psychology
2
301 - Sociology & anthropology
2
304 - Factors affecting social behavior
2
540 - Chemistry & allied sciences
2
550 - Earth sciences
2
004 - Data processing & computer science
1
120 - Epistemology, causation & humankind
1
200 - Religion
1
297 - Islam, Babism & Bahai Faith
1
331 - Labor economics
1
341 - Law of nations
1
346 - Private law
1
350 - Public administration & military science
1
361 - Social problems & social welfare in general
1
364 - Criminology
1
384 - Communications; telecommunication
1
510 - Mathematics
1
511 - General principles of mathematics
1
516 - Geometry
1
599 - Mammals
1
657 - Accounting
1
more ...