Gardiner, William P.
Prentice-Hall, 1997
Buku Teks
Dover Publications , 1971
Buku Teks
Fakultas Ilmu Komputer Universitas Indonesia, 1997
UI - Skripsi Membership
Arnold, Robert R.
John Wiley & Sons, 1978
Buku Teks SO
Brooks, Frederick P. Jr.
John Wiley & Sons, 1969
Buku Teks