Classification
330 - Economics
363 - Other social problems & services
600 - Technology
333 - Economics of land & energy
4
620 - Engineering & allied operations
4
900 - History & geography
4
700 - The arts; fine & decorative arts
3
000 - Computer science, information & general works
2
370 - Education
2
380 - Commerce, communications & transportation
2
580 - Plants (Botany)
2
140 - Specific philosophical schools
1
160 - Logic
1
400 - Language
1
410 - Linguistics
1
500 - Natural sciences & mathematics
1
551 - Geology, hydrology & meteorology
1
610 - Medicine & health
1