Oboronni zamky zakhidnoho Podilli︠a︡ XIV – XVII st. : (istorychno-arkheolohichni narysy) / I︠U︡khym Sit︠s︡insʹkyĭ. (OCLC #32649823)
This title is about castles and fortifications in a city in Ukraine:
650 _0 ǂa Fortification ǂz Ukraine ǂz Podillia. 650 _0 ǂa Castles ǂz Ukraine ǂz Podillia.
The LC classification NA1455.A-Z is for Architecture of special countries—Europe with NA1455.U47 specifically being for Ukraine. This class number is subarranged using Table N15, which includes the somewhat cryptic:
.x2A-x2Z Local, A-Z
This means that to specify a narrower location than Ukraine, append 2 to Ukraine’s cutter, and add a second cutter for that location (Podilla):
050 _4 ǂa NA1455.U472 ǂb P6357 1994
As a local practice, we always use the publication year in monograph call numbers when possible.