Classification
AAA - Encyclopedias - general aspects
113
CWA - Chemical engineering - reference books
95
ZAA - Books - general
66
PAA - Physics - reference books
59
CAA - Chemistry - reference books
31
HAA - Medicine - reference books
31
LAA - Biology - reference books
30
CTA - Chemical analysis - comprehensive works
28
UAA - Environment - reference books
26
MAA - Mathematics - reference books
25
FAA - Materials research - reference books
24
UAD - Environment - comprehensive works
22
EFA - Petroleum, natural gas
21
AYA - Sciences - general aspects
20
CNH - Electrochemistry - reference books
20
ABD - National biographic catalogues - Germany
18
EAA - Energy - reference books
13
GAA - Geosciences - reference books
13
MWH - Statistics
12
UMA - Atmospheric sciences
12
CELC - Organic synthesis
11
CEO - Natural organic products
11
CXUX - Natural products
11
LGA - Zoology - reference books
11
ACZ - Lists of abbreviations
10
FGN - Nanotechnology
10
FNF - Polymer science - general aspects
10
LEO - Chemical compounds from plants
10
LKH - Biochemistry - methods
10
PEG - Optics
10
UAM - Environmental models
10
UAN - Environment - mathematical methods, computer applications
10
CUW - Mass spectroscopy
9
DAA - Information technology - reference books
9
CAV - Chemicals, chemical reagents
8
CBB - Inorganic chemistry - comprehensive works
8
FAAC - Engineering materials - reference books
8
FAAE - Nonmetallic materials - reference books
8
FFM - Liquid interfaces, adhesion
8
LWA - Agriculture - reference books
8
TAA - Engineering sciences - reference books
8
UCS - Environmental chemistry
8
CUA - Spectroscopy
7
DYA - Artificial intelligence
7
FNV - Composite materials, fiber materials
7
LCP - Limnology
7
THA - Mechanical engineering - general
7
UMB - Atmospheric chemistry
7
UMV - Climatic change
7
FAAB - Solid state physics - reference books
6
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