Lesourne, Jacques
Englewood Cliffs, N.J., Prentice-Hall
Buku Teks
Rees, Bill
Prentice-Hall, 1990
Buku Teks
Scherer, F. M., author
Rand McNally , 1970
Buku Teks
Marglin, Stephen A., author
MIT Press, 1972
Buku Teks
Flanagan, Robert J.
Scott, Foresman, 1984
Buku Teks