Sherman, Howard J.
Harper and Row, 1989
Buku Teks
Cuff, E.C.
Routledge, 1995
Buku Teks
edited by Kenneth Thomson and Jeremy Tunstall
Penguin Books, 1983
Buku Teks
edited by E.C. Cuff; G.C.F. Payne
George Allen and Unwin, 1984
Buku Teks SO
Ross, H. Laurence (Hugh Laurence)
McGraw-Hill, 1973
Buku Teks