Columbia subject headings:
Harvard subject headings:
Educators--Switzerland--Correspondence.
Gysin, Alfred, 1883-1964--Correspondence.
Russia--History--20th century--Sources.
Russia--Relations--Switzerland.
Switzerland--Relations--Russia.
Princeton subject headings:
Educators--Switzerland--Correspondence.
Gysin, Alfred, 1883-1964--Correspondence.
Personal correspondence.
Russia--Description and travel.
Russia--History--1904-1914--Sources.
Russia--Relations--Switzerland.
Switzerland--Relations--Russia.