Columbia subject headings:
Harvard subject headings:
Bulgaria--History--1762-1878.
Eastern question (Balkan)
Russo-Turkish War, 1877-1878--Campaigns--Bulgaria.
Princeton subject headings:
Bulgaria--History--1762-1878--Sources.
Russia--History--Alexander II, 1855-1881--Sources.
Russo-Turkish War, 1877-1878--Participation, Bulgarian.
Turkey--History--1829-1878--Sources.