Slack, John M.
Burgess Publishers, 1971
Buku Teks
Willey, Joanne M., author
Mc Graw Hill, 2008
Buku Teks
Delant, Adrian N., author
Lea and Febiger, 1984
Buku Teks
Fuerst, Robert, author
W.B. Saunders , 1983
Buku Teks
William Bawen Sarles ...[et.al.]
Harper & Row, 1956
Buku Teks