Stone, Carolyn R.
Wren Publishing, 1974
Buku Referensi
Hetherington, John, author
Cheshire, 1960
Buku Teks
Hope, A.D., author
Oxford University Press, 1992
Buku Teks
FitzGerald, Robert David, 1902-, author
Angus & Robertson, 1963
Buku Teks
Balnaves, John
Cheshire , 1966
Buku Teks