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Buku Teks
edited by Charles F. Herman, Charles W. Kegley, James N. Rosenau
Harper Collins Academic, 1987
Buku Teks
edited by Anne Digby, Charles Feinstein and David Jenkins
Macmillan, 1992
Buku Teks
edited by Gian-Vittorio Caprara and Guus L. Van Heck
Harvester Wheatsheaf, 1992
Buku Teks
edited by G. Goodwin
Cambridge University Press, 1958
Buku Teks