Methuen & Co., Ltd., 1963
Buku Teks
Lerner, Laurence D., author
Oxford University Press, 1954
Buku Teks
Marsh, Nicholas
Higher and Further Education , 1987
Buku Teks
Drake, Henry Burgess, author
Oxford University Press, 1951
Buku Teks
Drake, Henry Burgess, author
Oxford University, 1957
Buku Teks