Submitted on: 15 December 2012.
Revised on: 20 January 2013.
Accepted on: 11 February 2013.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
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Submitted on: 05 October 2016.
Revised on: 26 January 2017.
Accepted on: 12 March 2017.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
Submitted on: 11 August 2015.
Revised on: 01 December 2015.
Accepted on: 15 January 2016.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
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Submitted on: 22 September 1999.
Revised on: 04 November 1999.
Accepted on: 29 November 1999.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
Submitted on: 29 May 2002.
Revised on: 02 August 2002.
Accepted on: 22 September 2002.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
Submitted on: 30 January 2010.
Revised on: 29 May 2010.
Accepted on: 24 June 2010.
___________________JOURNAL OF PURE AND APPLIED ALGEBRA
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