Columbia subject headings:
Revolutionaries--Russia--Biography.
Sozonov, Egor Sergeevich, 1879-1910--Correspondence.
Harvard subject headings:
Revolutionaries--Russia--Correspondence
Russia--History--Nicholas II, 1894-1917--Sources.
Sozonov, Egor Sergeevich, 1879-1910--Correspondence.
Terrorists--Russia--Correspondence.
Princeton subject headings:
Revolutionaries--Russia--Correspondence.
Russia--History--Nicholas II, 1894-1917--Sources.
Sozonov, Egor Sergeevich, 1879-1910--Correspondence.
Terrorists--Russia--Correspondence.