Gear, Jolene, author
Cambridge university press, 2010
Buku Teks
Dhanny R. Cyssco, author
Puspa Swara, 2004
Buku Teks
Sukur, Silvester Goridus, author
Buku Teks
Pyle, Michael A., author
Cliffs Notes, 1995
Multimedia
Pyle, Michael A., author
Cliffs, 1995
Multimedia