Michels, Leo, author
Brooks/Cole, 1993
Buku Teks
Michels, Leo, author
Brooks/Cole, 1996
Buku Teks
Lippincott, W.T., author
John Wiley & Sons, 1977
Buku Teks
Morrison, Robert Thornton, author
Prentice-Hall, 1992
Buku Teks
Morrison, Robert Thornton, author
Allyn and Bacon, 1973
Buku Teks