Giallombardo, Rose, author
John Wiley & Sons, 1982
Buku Teks
Kaplan, Howard B., author
Sage Publications, 1984
Buku Teks
Terrance M. Brungardt
Houghton Miffiln, 1983
Buku Teks
Yablonsky, Lewis, author
Wadsworth, 2000
Buku Teks
Trojanowicz, Robert C., 1941-, author
Prentice-Hall, 1987
Buku Teks