Saunders Elsevier, 2014
Buku Teks
Calder, Ritchie
The university Chichago Press, 1962
Buku Teks
Calder, Nigel
J. Munroe & company, limited, 1927
Buku Teks
Gibb, Donald
Butterworth-Heinemann , 2000
Buku Teks
Calder, Ritchie
Penguin Books, 1970
Buku Teks