Boston: Houghton: 1993,
Buku Referensi
Stroman, James, author
[American Management Association;, ], 2012
eBooks
Morton, Joyce, author
Prentice Hall Career & Technology, 1993
Buku Teks
Morton, Joyce, author
Prentice-Hall, 1998
Buku Teks
Doris, Lillian
Prentice-Hall, 1960
Buku Teks