Classification
140 - Specific philosophical schools
330 - Economics
333 - Economics of land & energy
2
361 - Social problems & social welfare in general
600 - Technology
2
658 - General management
000 - Computer science, information & general works
1
320 - Political science
1
336 - Public finance
1
363 - Other social problems & services
1
380 - Commerce, communications & transportation
1
500 - Natural sciences & mathematics
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1
800 - Literature & rhetoric
1