Montgomery, Glenn E., author
GIS World, Inc., 1993
Buku Referensi
Van Duyn, Julia, author
Prentice-Hall, 1982
Buku Teks
Lefkovits, Henry C., author
Information Sciences Inc., 1977
Buku Teks
Novrita Andriani, author
Fakultas Ilmu Komputer Universitas Indonesia, 1995
UI - Skripsi (Membership)
Leong-Hong, Belkis W., author
John Wiley , 1982
Buku Teks