Kirkham, George L.
Harper & Row, Publishers, 1980
Buku Teks
Berg, Bruce L. (Bruce Lawrence), 1954-, author
Allyn and Bacon, 1992
Buku Teks
Trautman, Neal E., author
Charles C Thomas Publisher, 1990
Buku Teks
Germann, A.C., author
C.C. Thomas, 1971
Buku Teks
White, Jonathan Randall, author
Wardsworth, 2004
Buku Teks