Columbia subject headings:
Harvard subject headings:
Anarchists--Switzerland--Biography.
Brupbacher, Fritz--Correspondence.
Brupbacher, Fritz.
Kotschetkowa, Lidija Petrowna, 1872-1921--Correspondence.
Kotschetkowa, Lidija Petrowna, 1872-1921.
Socialists--Russia--Biography.
Princeton subject headings:
Anarchists--Switzerland--Biography.
Brupbacher, Fritz.
Kotchekova, Lidii︠a︡ Petrovna, 1872-1921.
Revolutionaries--Russia--Biography.
Revolutionaries--Russia--Correspondence.
Socialists--Switzerland--Biography.
Socialists--Switzerland--Correspondence.