Springer, 2016
Buku Teks
Ur, Penny, author
Cambridge University Press, 1999
Buku Teks
Ur, Penny, author
Cambridge University Press, 1991
Buku Teks
Ur, Penny, author
Cambridge University Press, 2006
Buku Teks
Rivers, Wilga M., author
Cambridge University Press, 1994
Buku Teks