Hehman, Robert F., author
Costomized Publishing Division, 1976
Buku Teks
Yarbrough, James D., author
Burgess Publishing, 1970
Buku Teks
Murray, P. D. F. (Patrick Desmond Fitzgerald)
Macmillan, 1961
Buku Teks
Beck, Raymond W., author
Burgess, 1977
Buku Teks
Solomon, Eldra Pearl, author
Saunders College, 1995
Buku Teks