edited by Arthur J. Reynolds, Arthur J. Rolnick and Judy A. Temple
Cambridge University Press, 2014
Buku Teks SO
Robertson, Cathie, 1946-
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Buku Teks SO
Gilbert, Glen G.
Jones and Burtlet, 2011
Buku Teks SO
Porterfield, John D.
Voice American Forum Lecture, [Date of publication not identified]
Buku Teks
Shields, James J,Jr
Frederick A. Preager, 1967
Buku Teks