Pough, F. Harvey
Prentice-Hall, 1996
Buku Teks
Pough, F. Harvey
Prentice-Hall, 1999
Buku Teks
Orr, Robert T.
Saunders, 1976
Buku Teks
editors, Norman K. Wessells, Elizabeth M. Center
William Kaufmann, 1973
Buku Teks
Young, J.Z.
At The Clarendon Press, 1962
Buku Teks