Submitted on: 31 January 2009.
Revised on: 05 March 2009.
Accepted on: 15 April 2009.
___________________International Journal of Sustainable Energy
Submitted on: 17 March 2015.
Revised on: 13 July 2015.
Accepted on: 15 August 2015.
___________________International Journal of Sustainable Energy
Submitted on: 02 September 2011.
Revised on: 24 November 2011.
Accepted on: 16 December 2011.
___________________International Journal of Sustainable Energy
Submitted on: 15 September 1998.
Revised on: 10 November 1998.
Accepted on: 07 January 1999.
___________________International Journal of Sustainable Energy
Submitted on: 01 April 2001.
Revised on: 21 May 2001.
Accepted on: 30 June 2001.
___________________International Journal of Sustainable Energy
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