Artikel Jurnal
Vinod Thomas [and others]
Gramedia Pustaka Utama, 2001
Buku Teks
Emilla Melati, author
2016
UI - Tesis (Membership)
Weil, David N., author
Pearsons Addison-Wesley, 2009
Buku Teks
Eltis, W.A.
Hutchinson University Library , 1966
Buku Teks