Stewart, Valerie
Change : the challenge for management
McGraw-Hill, 1983
 Buku Teks
Indonesia : the challenge of change
edited by Richard W. Baker [and others]
Institute of Southeast Asian Studies, 1999
 Buku Teks
Challenge and change in the information society
edited by Susan Hornby, Zoe Clarke
Facet, 2004
 Buku Teks
Saaty, Thomas L.
Embracing the future : meeting the challenge of our changing world
Praeger, 1990
 Buku Teks
Christenson, Reo M.
Challenge and decision : political issues of our time / Reo M. Christenson
Harper & Row Publishers, 1982
 Buku Teks