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Submitted on: 28 October 1999.
Revised on: 12 January 2000.
Accepted on: 01 February 2000.
___________________Channels---TAYLOR & FRANCIS INC
Submitted on: 10 November 2017.
Revised on: 13 February 2018.
Accepted on: 08 April 2018.
___________________Channels---TAYLOR & FRANCIS INC