Classification
900 - History & geography
363 - Other social problems & services
11
330 - Economics
5
700 - The arts; fine & decorative arts
5
301 - Sociology & anthropology
4
320 - Political science
3
414 - Phonology & phonetics
3
581 - Specific topics in natural history
3
100 - Philosophy & psychology
2
361 - Social problems & social welfare in general
2
590 - Animals (Zoology)
2
780 - Music
2
140 - Specific philosophical schools
1
200 - Religion
1
304 - Factors affecting social behavior
1
333 - Economics of land & energy
1
340 - Law
1
370 - Education
1
400 - Language
1
410 - Linguistics
1
540 - Chemistry & allied sciences
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1
600 - Technology
1
620 - Engineering & allied operations
1
630 - Agriculture & related technologies
1
770 - Photography, photographs & computer art
1
800 - Literature & rhetoric
1