Sharp, Henry, author
Prentice-Hall, 1968
Buku Teks
Keedy, Mervin J., author
Addison-Wesley , 1969
Buku Teks
Fine, Nathan J., author
Rand McNally, 1965
Buku Teks
Fine, Nathan J., author
Rand McNally, 1965
Buku Teks
Wheeler, Ruric E., author
Brooks/Cole, 1967
Buku Teks