Shidle, Norman G., author
McGraw-Hill, 1951
Buku Teks
Messenger, William E., author
Prentice-Hall, 1989
Buku Teks
Haslam, Sara, author
Routledge, 2009
Buku Teks
Bramer, George R., author
Charles E. Merrill Publishing Company, 1981
Buku Teks
Staff of Research and Education Association; M. Fogiel, director
Research and Education Association, 1991
Buku Teks