Takaful Islamic insurance: concepts and regulatory issues
edited by Simon Archer, Rifaat Ahmed Abdel Karim, Volker Nienhaus
John Wiley & Sons (Asia), 2009
 Buku Teks
Japan's small business the new challenge
Japan Small Business Research Institute , 1995
 Buku Teks
New horizons for the information profession : meeting the challenge of change
edited by Hilary Dyer and Gwyneth Tseng
Taylor Graham, 1988
 Buku Teks
Beirne, Joseph A.
Challenge to Labor new roles for American trade unions
Prentice-Hall, 1969
 Buku Teks
Godfrey, Martin
Global unemployment: the new challenge to economic theory
St. Martin's Press, 1985
 Buku Teks