Diggins, J. P. (1973). The american left in the twentieth century. Harcourt, Brace, Jovanovich.
Lua i Stíl Chicago (17ú heag.)Diggins, John P. The American Left in the Twentieth Century. New York [u.a.]: Harcourt, Brace, Jovanovich, 1973.
Lua MLA (8ú heag.)Diggins, John P. The American Left in the Twentieth Century. Harcourt, Brace, Jovanovich, 1973.
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