Yahuda, Michael
Hong Kong : China's challenge
Routledge, 1996
 Buku Teks
Mahathir bin Mohamad, 1925-
The challenge
Pelanduk Publications, 1986
 Buku Teks
Seo Hajin
Hong Gildon
Jimoondang Publishing Company, 2007
 Buku Teks
Myrdal, Gunnar, 1898-
Challenge to affluence
Pantheon Books, 1963
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Engler, Richard E.
The challenge of diversity
Harper & Row, 1964
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