Classification
ACA - Languages, dictionaries - general
1
ACE - Germanic languages, Indo-Germanic languages
1
DOF - Programming language - C, Turbo C, C# (C sharp)
1
DOR - Programming languages - JAVA, C#, Mono, .NET
1
PKB - Elementary particles, nuclei - comprehensive works
1
TAA - Engineering sciences - reference books
1
TBC - Electronic circuits
1