Columbia subject headings:
Harvard subject headings:
Bulgaria--Civilization--Congresses.
Bulgarian literature--19th century--History and criticism--Congresses.
Bulgarian literature--20th century--History and criticism--Congresses.
Bulgarian literature--European influences--Congresses.
Bulgarian literature--History and criticism--Congresses.
Modernism (Literature)--Bulgaria--Congresses.
Princeton subject headings:
Bulgarian literature--19th century--History and criticism--Congresses.
Bulgarian literature--20th century--History and criticism--Congresses.