Classification
363 - Other social problems & services
3
551 - Geology, hydrology & meteorology
576 - Genetics & evolution
600 - Technology
620 - Engineering & allied operations
3
700 - The arts; fine & decorative arts
900 - History & geography
140 - Specific philosophical schools
1
320 - Political science
1
333 - Economics of land & energy
1
380 - Commerce, communications & transportation
1
581 - Specific topics in natural history
1