Kennedy, Dora, author
National Texbook, 1994
Buku Teks
Artikel Jurnal
Badib, Abbas A., author
2005
Artikel Jurnal
edited by Janet l. Nicol
Blackwell , 2006
Buku Teks
Allen, Edward David, author
Harcourt Brace Jovanovich, [Date of publication not identified]
Buku Teks