Submitted on: 08 July 2019.
Revised on: 19 July 2019.
Accepted on: 13 August 2019.
NULL
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http://reply.papertrans.cn/3/211/21038/21038-33.png
Submitted on: 04 March 2011.
Revised on: 18 March 2011.
Accepted on: 26 March 2011.
NULL
Submitted on: 15 October 1999.
Revised on: 01 November 1999.
Accepted on: 13 November 1999.
LOISIR & SOCIETE-SOCIETY AND LEISURE
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