Classification
333 - Economics of land & energy
551 - Geology, hydrology & meteorology
600 - Technology
000 - Computer science, information & general works
3
620 - Engineering & allied operations
3
700 - The arts; fine & decorative arts
3
900 - History & geography
3
363 - Other social problems & services
2
530 - Physics
2
800 - Literature & rhetoric
2
304 - Factors affecting social behavior
1
320 - Political science
1
330 - Economics
1
370 - Education
1
380 - Commerce, communications & transportation
1
414 - Phonology & phonetics
1
580 - Plants (Botany)
1
630 - Agriculture & related technologies
1