Burgess, Giles H., author
Prentice-Hall, 1989
Buku Teks
Koch, James V., author
Prentice-Hall, 1980
Buku Teks
Shepherd, William G., author
Prentice-Hall, 1979
Buku Teks
Waldman, Don E., author
Pearson, 2007
Buku Teks
Scherer, F. M., author
Rand McNally , 1970
Buku Teks