Wood, Harley
Angus and Robertson, 1967
Buku Teks
Hartman, William K., author
Wadsworth, 1985
Buku Teks
Robbins, Robert R., author
John Wiley & Sons, 1981
Buku Teks
Sybil P. Parker, editor in chief
McGraw-Hill, 1997
Buku Referensi
Mitton, Jacqueline, author
Oxford University Press, 1991
Buku Referensi