Columbia subject headings:
Bulgarian language.
Nit︠s︡olova, Ruselina Lozanova--Bibliography.
Slavic languages, Southern.
Slavic languages.
Harvard subject headings:
Bulgarian language.
Bulgarian philology.
Princeton subject headings:
Bulgarian language.
Nit︠s︡olova, Ruselina Lozanova--Bibliography.
Slavic languages, Southern.
Slavic languages.