Hill, W. F.
Garden Art Press, 1995
Buku Referensi
Macmillan Press, Ltd., 1994
Buku Teks
Jelliffe, D. B.
Edward Arnold, 1985
Buku Teks
edited by J.R. Landon
Longman Scientific & Technical, 1984
Buku Referensi
Murnane, Gerald
Penguin Books, 1987
Buku Teks