Kothari, C.R.
Vikas Publishing House, 1978
Buku Teks
Reinke, William A.
The John Hopkins University Press , 1972
Buku Teks
Biegel, John E.
Prentice-Hall, 1978
Buku Teks
Bartholomae, David J.
John Wiley & Sons, 1979
Buku Teks
Immer, John R.
McGraw-Hill, 1950
Buku Teks