Columbia subject headings:
Harvard subject headings:
Alaska--Discovery and exploration--Sources.
Discoveries in geography--Russian--Sources.
Northwest, Pacific--Discovery and exploration--Sources.
Russia--Territorial expansion--Sources.
Russian Far East (Russia)--Discovery and exploration--Sources.
Princeton subject headings:
Alaska--Discovery and exploration--Sources.
Discoveries in geography--Russian--Sources.
Northwest, Pacific--Discovery and exploration--Sources.
Russia--Territorial expansion--Sources.
Russian Far East (Russia)--Discovery and exploration--Sources.