Cash, Phyllis
Monarch Press, 1977
Buku Teks
Purves, Alan C. (Alan Carroll), 1931-1996
Harcourt Brace Jovanovich, 1984
Buku Teks SO
Tilley, Andrew J.
Pineapple Press, 2003
Buku Teks
Antoni Ludfi Arifin
Gramedia Pustaka Utama , 2012
Buku Teks
Berry, Ralph
London : ROUTLEDGE, 1994,
Buku Referensi