Submitted on: 28 July 2001.
Revised on: 29 August 2001.
Accepted on: 10 October 2001.
___________________COMMUNICATIONS IN ALGEBRA---TAYLOR & FRANCIS INC
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Submitted on: 03 September 2001.
Revised on: 11 October 2001.
Accepted on: 05 December 2001.
___________________COMMUNICATIONS IN ALGEBRA---TAYLOR & FRANCIS INC
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Submitted on: 07 June 2015.
Revised on: 14 July 2015.
Accepted on: 12 September 2015.
___________________COMMUNICATIONS IN ALGEBRA---TAYLOR & FRANCIS INC
Submitted on: 27 December 2007.
Revised on: 23 March 2008.
Accepted on: 02 May 2008.
___________________COMMUNICATIONS IN ALGEBRA---TAYLOR & FRANCIS INC