Columbia subject headings:
Bulgarian literature--20th century--History and criticism.
Comparative literature--Bulgarian and Russian.
Comparative literature--Russian and Bulgarian.
Russian literature--20th century--History and criticism.
Harvard subject headings:
Bulgarian literature--20th century--History and criticism.
Comparative literature--Bulgarian and Russian.
Comparative literature--Russian and Bulgarian.
Russian literature--20th century--History and criticism
Princeton subject headings:
Bulgarian literature--20th century--History and criticism.
Comparative literature--Bulgarian and Russian.
Comparative literature--Russian and Bulgarian.
Russian literature--20th century--History and criticism.