Gabriel, Ralph Henry, 1890-1987, author
D. Appleton-Century, 1942
Buku Teks
Herget, James E., author
Rice University Press, 1990
Buku Referensi
Kennedy, David M., 1905-1996, author
Wadsworth and Cengage Learning, 2012
Buku Teks
edited by Allen F. Davis and Harold D. Woodman
D.C. Health, 1984
Buku Teks
Hurst, James Willard, author
Little, Brown, 1950
Buku Teks