Some typical coding of Soviet military maps and battle schemes
A - Army
BAD - Breakthrough Artillery Division
CA - Coastal Army
DbF - Danube Flotilla
GAbnD - Guards Airborne Division
GRC - Guards Rifle Corps
RC - Rifle Corps
RD - Rifle Division
UF - Ukrainian Front
YA - Yugoslavian Army
Perechnev Yu.G., Sovetskaya beregovaya artilleriya: Istoriya razvitiya i boyevogo primeneniya 1921-1945 gg, Moskva, Nauka, 1976 (cited from militera.lib.ru)
"Taktika v boyevykh primerakh. Batalion", Moskva, Voyenizdat, 1974 (cited from docs.vif2.ru).
Blazhei A.K., "V Armejskom shtabe", Moskva, Voyenizdat, 1967 (cited from militera.lib.ru)