Helen L. Van Hoozer [and others]
Appleton Century Crofts, 1987
Buku Teks
Ur, Penny
Cambridge University Press, 2006
Buku Teks
Ur, Penny
Cambridge University Press, 1999
Buku Teks
inda Gask, Bulent Coskun, David Baron
Wiley- Blackwell, 2011
Buku Teks
Ur, Penny
Cambridge University Press, 1991
Buku Teks