Dalrymple, Douglas J.
John Wiley & Sons, 1983
Buku Teks
Gandhi, J.C.
McGraw-Hill Publishing Company, 1995
Buku Teks
Peter, J. Paul
McGraw-Hill, 2004
Buku Teks
Boyd, Harper W., Jr.
New York, N.Y. , Harcourt Brace Jovanovich
Buku Teks
Charvat, Frank J.
Heath, 1966
Buku Teks