Columbia subject headings:
Poets, Russian--20th century--Correspondence.
Ėfron, Ariadna, 1912-1975--Correspondence.
Harvard subject headings:
Poets, Russian--20th century--Correspondence
Ėfron, Ariadna, 1912-1975--Correspondence.
Princeton subject headings:
Ėfron, Ariadna, 1912-1975--Correspondence.
Poets, Russian--20th century--Correspondence.