Doris, Lillian, author
Prentice-Hall, 1970
Buku Referensi
Rose, La, author
Erlangga, 2003
Buku Teks
Hirschheim, R.A
Addison-Wesley, 1986
Buku Teks
Levin, Howard S., author
John Wiley & Sons, 1956
Buku Teks
Lieberman, Mark A.
Jaohn Wiley & Sons, 1982
Buku Teks