Michels , . R. (1968). Political parties: A sociological study of the Oligarchical tendencies of modern democracy (2nd ed.). Free Press.
Chicago-viite (17. p.)Michels , Robert. Political Parties: A Sociological Study of the Oligarchical Tendencies of Modern Democracy. 2nd ed. New York: Free Press, 1968.
MLA-viite (9. p.)Michels , Robert. Political Parties: A Sociological Study of the Oligarchical Tendencies of Modern Democracy. 2nd ed. Free Press, 1968.
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