Athur L. Anger...[et.al]
John Wiley & Sons, 1972
Buku Teks
Jakarta : Pt.Elex Media Komputindo, 2006,
Majalah, Jurnal, Buletin
UI - Publikasi
Downing, Douglas, author
Elex Media Komputindo, 1993
Buku Teks
Arnold, A., author
Prentice-Hall, 1996
Buku Teks