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Submitted on: 19 March 2012.
Revised on: 29 March 2012.
Accepted on: 20 April 2012.
Korean Journal of Mathematics
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Submitted on: 21 July 2009.
Revised on: 20 August 2009.
Accepted on: 07 September 2009.
Korean Journal of Mathematics
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Submitted on: 20 December 2000.
Revised on: 24 January 2001.
Accepted on: 06 February 2001.
Korean Journal of Mathematics---KANGWON-KYUNGKI MATHEMATICAL SOC
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Submitted on: 31 December 2000.
Revised on: 16 January 2001.
Accepted on: 21 January 2001.
Korean Journal of Mathematics---KANGWON-KYUNGKI MATHEMATICAL SOC
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