Proctor, W. M. (1929). Vocations: The world's work and its workers. Houghton Mifflin Company.
Chicago-viite (17. p.)Proctor, William Martin. Vocations: The World's Work and Its Workers. Boston : New York [etc.]: Houghton Mifflin Company, 1929.
MLA-viite (8. p.)Proctor, William Martin. Vocations: The World's Work and Its Workers. Houghton Mifflin Company, 1929.
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