Classification
170 - Ethics
333 - Economics of land & energy
370 - Education
2
530 - Physics
600 - Technology
2
700 - The arts; fine & decorative arts
000 - Computer science, information & general works
1
120 - Epistemology, causation & humankind
1
140 - Specific philosophical schools
1
304 - Factors affecting social behavior
1
320 - Political science
1
330 - Economics
1
340 - Law
1
551 - Geology, hydrology & meteorology
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
620 - Engineering & allied operations
1
900 - History & geography
1