Sheryn, Hinton J.
Surrey : Ian Alla, 1995
Buku Teks
Weller, J. Marvin
McGraw-Hill, 1969
Buku Teks
Tarasoff, Koozma J.
Prairie Book Dept., Western Producer, 1969
Buku Teks
Lutgens, Frederick K.
Prentice-Hall, 2008
Buku Teks
Reid, Robin, author
Churchill Livingstone, 2008
Buku Teks