Hughes, Charles W.
Columbia University Press, 1980
Buku Referensi
Hughes, Charles W.
Columbia University Press, 1980
Buku Referensi
Tomasowa, Francien Herlen
Universitas Brawijaya , 2005
Buku Teks SO
Eckersley, C. E. (Charles Ewart), 1892-1967
Longmans, Green and Co., 1953
Buku Referensi
McCrum, Robert
Faber and Faber , 1992
Buku Teks SO