Beevers, Harry Professor.
Harper & Row,, 1961
Buku Teks
Blackman, Carolyn
Allen & Unwin, 1997
Buku Teks
Blackman, Barbara
Viking, 1998
Buku Teks
Agrawal, K.C.
Agro Botanical Publishers, 1989
Buku Teks
Blackman, Barbara
Penguin Books , 1997
Buku Teks