Knauth, Oliver D.
Nasional Planning Association, 1960
Buku Teks
Langdon, Robert M., author
Littlefield Adams, 1961
Buku Teks
Pratt, Julius W., author
Prentice-Hall, 1965
Buku Teks
Leopold, Richard W., author
Alfred A. Knopf, 1962
Buku Teks
London, Kurt
D.van Nostrand Company,Inc., 1950
Buku Teks