Columbia subject headings:
Church Slavic language--Russian recension.
Diglossia (Linguistics)--Russia--History.
Russian language--1300-1700--History.
Russian language--History.
Russian language--Standardization.
Russian language--To 1300--History.
Harvard subject headings:
Russian language--History.
Russian language--Standardization.
Princeton subject headings:
Church Slavic language--Russian recension--History.
Russian language--History.