Classification
000 - Computer science, information & general works
630 - Agriculture & related technologies
363 - Other social problems & services
22
333 - Economics of land & energy
19
580 - Plants (Botany)
19
330 - Economics
18
600 - Technology
18
700 - The arts; fine & decorative arts
18
551 - Geology, hydrology & meteorology
17
620 - Engineering & allied operations
14
581 - Specific topics in natural history
12
610 - Medicine & health
11
320 - Political science
10
140 - Specific philosophical schools
7
304 - Factors affecting social behavior
7
370 - Education
3
540 - Chemistry & allied sciences
3
340 - Law
2
361 - Social problems & social welfare in general
2
380 - Commerce, communications & transportation
2
658 - General management
2
800 - Literature & rhetoric
2
170 - Ethics
1
300 - Social sciences
1
336 - Public finance
1
414 - Phonology & phonetics
1
520 - Astronomy & allied sciences
1
576 - Genetics & evolution
1
612 - Human physiology
1
720 - Architecture
1
900 - History & geography
1