Columbia subject headings:
Historians--Canada--Directories.
Historians--United States--Directories.
History--Societies, etc.--Directories.
History--Study and teaching (Higher)--Canada--Directories.
History--Study and teaching (Higher)--United States--Directories.
Harvard subject headings:
Historians--Canada--Directories.
Historians--United States--Directories.
History--Societies, etc.--Directories.
History--Study and teaching (Higher)--Canada--Directories.
History--Study and teaching (Higher)--United States--Directories.
Princeton subject headings:
Directories.
Historians--Canada--Directories.
Historians--United States--Directories.
History--Societies, etc.--Directories.
History--Study and teaching (Higher)--Canada--Directories.
History--Study and teaching (Higher)--United States--Directories.