Columbia subject headings:
Bŭlgarska komunisticheska partii︠a︡--History.
Varna (Bulgaria : Oblast)
World War, 1939-1945--Underground movements--Bulgaria--Varna (Oblast)
Harvard subject headings:
Bŭlgarska komunisticheska partii︠a︡--History.
Varnenska oblast (Bulgaria)--History.
World War, 1939-1945--Underground movements--Bulgaria--Varnenska oblast.
Princeton subject headings: