http://reply.papertrans.cn/3/227/22632/22632-31.png
Submitted on: 20 May 2002.
Revised on: 26 June 2002.
Accepted on: 15 July 2002.
National Institute Economic Review
Submitted on: 17 March 2007.
Revised on: 18 April 2007.
Accepted on: 02 May 2007.
National Institute Economic Review
http://reply.papertrans.cn/3/227/22632/22632-34.png
http://reply.papertrans.cn/3/227/22632/22632-35.png
Submitted on: 14 August 2004.
Revised on: 24 September 2004.
Accepted on: 08 October 2004.
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