Classification
600 - Technology
630 - Agriculture & related technologies
900 - History & geography
620 - Engineering & allied operations
9
300 - Social sciences
3
330 - Economics
3
200 - Religion
2
800 - Literature & rhetoric
2
304 - Factors affecting social behavior
1
320 - Political science
1
333 - Economics of land & energy
1
380 - Commerce, communications & transportation
1
550 - Earth sciences
1
576 - Genetics & evolution
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1