Classification
330 - Economics
131
304 - Factors affecting social behavior
38
307 - Communities
38
320 - Political science
23
333 - Economics of land & energy
18
690 - Buildings
14
033 - Encyclopedias in other Germanic languages
12
338 - Production
9
300 - Social sciences
8
658 - General management
8
910 - Geography & travel
8
621 - Applied physics
7
629 - Other branches of engineering
6
700 - The arts; fine & decorative arts
6
720 - Architecture
6
140 - Specific philosophical schools
5
363 - Other social problems & services
5
000 - Computer science, information & general works
4
006 - Special computer methods
4
600 - Technology
4
301 - Sociology & anthropology
3
331 - Labor economics
3
500 - Natural sciences & mathematics
3
306 - Culture & institutions
2
339 - Macroeconomics & related topics
2
350 - Public administration & military science
2
351 - Public administration
2
628 - Sanitary & municipal engineering
2
696 - Utilities
2
900 - History & geography
2
003 - Systems
1
004 - Data processing & computer science
1
005 - Computer programming, programs & data
1
160 - Logic
1
170 - Ethics
1
337 - International economics
1
340 - Law
1
352 - General considerations of public administration
1
370 - Education
1
380 - Commerce, communications & transportation
1
530 - Physics
1
550 - Earth sciences
1
551 - Geology, hydrology & meteorology
1
620 - Engineering & allied operations
1
624 - Civil engineering
1
627 - Hydraulic engineering
1
630 - Agriculture & related technologies
1
641 - Food & drink
1
670 - Manufacturing
1
710 - Civic & landscape art
1
more ...