Aitkin, Don
Pitman, 1985
Buku Teks
Gwynneth Singleton ... [et al.]
Pearson, 2013
Buku Teks
Fried, Robert C.
Macmillan, 1968
Buku Teks
edited by Pierre Béguin
[Publisher not identified], [Date of publication not identified]
Buku Teks
Aitkin, Don
Pitman, 1985
Buku Teks