Collie, Joanne, author
Cambridge University Press, 1990
Buku Teks
Collie, Joanne, author
Cambridge University Press, 1987
Buku Teks
Siobhan Chapman
Oxford University Press, 2005
Buku Teks
Georgetown University Press, 1972
Buku Teks
Ruqaiya Hasan, author
Oxford University Press,, 1989
Buku Teks