Caiger, George
Columbia University Press, 1953
Buku Teks
McGraw-Hill, 1975
Buku Teks
Foster, Lois E. Elaine
Prentice-Hall, 1981
Buku Teks
Mol, Hans, 1922-, author
George Allen and Unwin, 1985
Buku Teks
edited by Donald McLean
Angus and Robertson, 1969
Buku Teks