Fisher, Ronald C.
Routledge, 2016
Buku Teks
Fisher, Ronald C.
Scott, Foresman, 1988
Buku Teks
Carr, Robert K.
University of Oklahoma Press, 1937
Buku Teks
Gelfand, M. David
West Publishing, 1986
Buku Teks
Marc Buggeln
Cambridge University Press, 2017
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