edited by Howard Newby
John Wiley & Sons, 1978
Buku Teks
Nelson, Lowry, author
American Book, 1955
Buku Teks
Cuff, E.C., author
Routledge, 1995
Buku Teks
edited by E.C. Cuff; G.C.F. Payne
George Allen and Unwin, 1984
Buku Teks
Loomis, Charles P., author
Prentice-Hall, 1957
Buku Teks