* Hyfler, Robert. ''Prophets of the Left: American Socialist Thought in the Twentieth Century'' (1984) 192 pp. [http://www.questia.com/read/15255158?title=Prophets%20of%20the%20Left%3a%20American%20Socialist%20Thought%20in%20the%20Twentieth%20Century online edition] | * Hyfler, Robert. ''Prophets of the Left: American Socialist Thought in the Twentieth Century'' (1984) 192 pp. [http://www.questia.com/read/15255158?title=Prophets%20of%20the%20Left%3a%20American%20Socialist%20Thought%20in%20the%20Twentieth%20Century online edition] |