Sharpe, Leslie T., author
Camberidge University Press , 1994
Buku Teks
Morrish, John, author
Routledge, 1996
Buku Teks
Gilmore, Gene, author
Body & Fraser Publishing Company, 1997
Buku Teks
Gilmore, Gene, author
The Glindersany, 1971
Buku Teks
Rivers, William L., author
Wadsworth, 1983
Buku Teks