Columbia subject headings:
Authors, Russian--Correspondence.
Blok, Aleksandr Aleksandrovich, 1880-1921.
Kli︠u︡ev, Nikolaĭ, 1884-1937--Correspondence.
Poets, Russian--20th century--Correspondence.
Harvard subject headings:
Blok, Aleksandr Aleksandrovich, 1880-1921
Kli︠u︡ev, Nikolaĭ, 1884-1937--Correspondence.
Poets, Russian--20th century--Correspondence
Princeton subject headings:
Blok, Aleksandr Aleksandrovich, 1880-1921.
Kli︠u︡ev, Nikolaĭ, 1884-1937--Correspondence.
Poets, Russian--20th century--Correspondence.