Submitted on: 05 August 1998.
Revised on: 10 October 1998.
Accepted on: 19 November 1998.
___________________Journal of Sustainable Metallurgy
Submitted on: 23 September 2002.
Revised on: 18 December 2002.
Accepted on: 16 January 2003.
___________________Journal of Sustainable Metallurgy
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Submitted on: 04 October 2003.
Revised on: 03 November 2003.
Accepted on: 31 December 2003.
___________________Journal of Sustainable Metallurgy
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