Classification
AES - Universities, academies - Germany
AHH - Universities - research
16
AHF - Research and science
5
AMA - Education - general
3
PKAE - Elementary particles, nuclei (reports)
3
YPGH - Planning and controlling
3
YRA - Social studies
3
AET - Universities, academies - Europe
2
AEX - Universities, academies - non-Europe
2
AFC - Research institutions, scientific organizations - Germany ( DFG, MPG, FHG )
2
AFK - Research institutions - Germany
2
GAN - Geosciences - mathematical methods, computer applications
2
GRA - Meteorology
2
LAD - Biology - comprehensive works
2
YPGD - Quality management
2
AEA - Corporations - official - university - etc
1
AHE - Research and development, research politics - foreign countries
1
AHK - Scientific work
1
AHM - Theory of science
1
AHZ - History of science and technology
1
AZZ - Firm index - general
1
UAA - Environment - reference books
1
UAX - Environment - information systems, literature guides
1
YDW - Foundation law
1
YKA - Criminal legislation
1
YPB - Economy - general aspects
1
YPC - Public administration
1
YPGB - Process management
1
YPGE - Human resource planning, human resource management
1
YPGL - Public relations
1
YRAF - Equal opportunities
1
YRAF - Equal opportunities
1
YRB - Social sciences, sociology
1
YRC - Technology and society
1