Juan, Stephen
Gramedia , 2005
Buku Teks SO
Anderson, Paul D.
EGC, 1996
Buku Teks
Pearce, Evelyn C. (Evelyn Clare)
Gramedia Pustaka Utama, 1979
Buku Teks SO
Pearce, Evelyn C. (Evelyn Clare)
Gramedia, 1991
Buku Teks SO
Anderson, Paul D.
EGC, 1996
Buku Teks