Ward, Barbara, author
W.W. Norton & Company, 1959
Buku Teks
Deutsch, Karl Wolfgang, 1912-1992, author
Technology Press of the Massachusetts Institute of Technology, 1953
Buku Teks
Ward, Barbara, author
University of Toronto Press , 1963
Buku Teks
Gellner, Ernest
Cornell University Press, 2008
Buku Teks
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Buku Teks