Classification
MDA - Foundations of mathematics
11
TAA - Engineering sciences - reference books
11
CAA - Chemistry - reference books
7
CBB - Inorganic chemistry - comprehensive works
7
MSD - Mathematical methods in physics
7
PAA - Physics - reference books
6
PGC - Physics of ionized gases, electric discharges
6
TNA - Nuclear engineering - general
6
CEC - Organic chemistry - comprehensive works
4
EAA - Energy - reference books
4
FLH - Low temperature technology, cryogenics
4
TKD - Air conditioning, refrigeration
4
YNA - Patents, trademarks
4
CB - Inorganic chemistry
3
CH - Physical chemistry
3
EWA - Energy economy
3
EXA - Energy policy
3
FDKB - Diffusion in condensed matter
3
PEC - Electromagnetic waves
3
TND - Gas cooled reactor types
3
YUG - Demography
3
ACE - Germanic languages, Indo-Germanic languages
2
ACH - Romance languages
2
CT - Chemical methods of materials analysis
2
CUW - Mass spectroscopy
2
DPA - Electronic data processing - applications
2
FAAC - Engineering materials - reference books
2
FAAD - Metallic materials - reference books
2
FMPJ - Steels and ferrous alloys for specific applications
2
FMXD - Metal hydrogen systems - general aspects
2
FPM - Materials testing - general aspects
2
LEM - Botany - anatomy, morphology
2
LWE - Agriculture - general aspects
2
MIDA - Analytical topology
2
MIDB - Algebraic topology
2
MIE - Functional analysis
2
MKAE - Stability theory - ODE
2
PKF - Elementary particles, nuclei - measuring methods and instruments
2
PKK - Theory of fields and particles - general
2
TBC - Electronic circuits
2
TBJ - Integrated circuits
2
TBS - Digital electronics
2
TGH - Technical optics
2
UA - Environment - general
2
UXU - Radioactive waste solidification
2
ACA - Languages, dictionaries - general
1
ACZ - Lists of abbreviations
1
AFM - Research institutions - Europe
1
AHF - Research and science
1
AHZ - History of science and technology
1
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