Dougan, Dennis L.
London Sweet & Maxwell, Limited 1951,
Buku Teks
Dougan, Dennis L.
Sweet & Maxwell , 1951
Buku Teks
Cousins, Donald, author
English Universities Press , 1955
Buku Teks
Wood, Frank
Pitman Pub., 1992
Buku Teks
Gee, Paul
Butterworth, 1994
Buku Teks