Gary Joseph, Georgina Carson, Phyllis Brodkin, William Abbott, Geuffrey Wells
Carswell, 2011
Buku Referensi
edited by W.A. Paton
Ronald Press, 1955
Buku Teks
Prentice-Hall, 1991
Buku Referensi
Frederick S. Merritt and Jonathan T. Ricketts, editor
McGraw-Hill, Inc, 1994
Buku Referensi
editor, Harry Helms [and others]
McGraw-Hill, 1983
Buku Referensi