Columbia subject headings:
Harvard subject headings:
Russian language--Aspect.
Russian language--Grammar, Comparative--Bulgarian.
Russian language--Grammar, Comparative--Slavic languages, Western.
Russian language--Verb.
Slavic languages--Aspect.
Slavic languages--Verb.
Princeton subject headings:
Russian language--Aspect.
Russian language--Grammar, Comparative--Bulgarian.
Russian language--Grammar, Comparative--Slavic languages, Western.
Russian language--Verb.
Slavic languages--Aspect.
Slavic languages--Verb.