Andrain, Charles F.
Macmillan, 1995
Buku Teks
Mason, Alpheus Thomas,1899-1989
Prentice-Hall, 1959
Buku Teks
Cohn, Theodore H.
Longman, 2003
Buku Teks
Andrew Light, editor; Avner de-Shalit, editor
MIT Press, 2003
Buku Teks
Swales, John M.
Cambridge University Press, 2004
Buku Teks SO