Columbia subject headings:
Authors, Canadian--20th century--Correspondence.
Mass media.
McLuhan, Marshall, 1911-1980--Correspondence.
Harvard subject headings:
Authors, Canadian--20th century--Correspondence.
Mass media specialists--Canada--Correspondence.
McLuhan, Marshall, 1911-1980--Correspondence.
Princeton subject headings:
Authors, Canadian--20th century--Correspondence.
Mass media.
McLuhan, Marshall, 1911---Correspondence.