Maidment, Frederick, author
Prentice-Hall, 2000
Buku Teks
Drucker, Peter F. (Peter Ferdinand), 1909-2005, author
Heinemann Profesional , 1990
Buku Teks
Beck, Roger
McGraw-Hill, 1978
Buku Teks
Ryan, Neal, author
Prentice-Hall, 2003
Buku Teks
Navarro, Vicente
Ballinger Publ., 1994
Buku Teks