Ross, Robert C.
McGraw-Hill, 1951
Buku Teks
Mellor, John W.
Cornell University Press, 1966
Buku Teks
Thomson, Edgar
Thomson Nelson and Sons Ltd. , 1949
Buku Teks
Elkan, Walter
The English Language Book Society ; Penguin Books, 1973
Buku Teks
Cramer, Gail L.
John Wiley & Sons, 1979
Buku Teks