Columbia subject headings:
Blok, Aleksandr Aleksandrovich, 1880-1921. Dvenadt︠s︡atʹ.
Harvard subject headings:
Blok, Aleksandr Aleksandrovich, 1880-1921. Dvenadt︠s︡atʹ
Princeton subject headings:
Blok, Aleksandr Aleksandrovich, 1880-1921. Dvenadt︠s︡atʹ.