Artikel Jurnal
Chowdhury, G.G., author
Facet Publishing, 2007
Buku Teks
Rama Pandugita, author
Fakultas Ilmu Komputer Universitas Indonesia, 2006
UI - Skripsi (Membership)
Allen, Jane Elizabeth
Addison-Wesley, 1987
Buku Teks
Jossey-Bass Inc., Publishers, 1990
Buku Teks