Submitted on: 27 May 2014.
Revised on: 29 August 2014.
Accepted on: 03 October 2014.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
Submitted on: 01 April 2008.
Revised on: 04 July 2008.
Accepted on: 20 July 2008.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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Submitted on: 14 November 2022.
Revised on: 18 January 2023.
Accepted on: 13 February 2023.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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Submitted on: 19 June 2003.
Revised on: 24 September 2003.
Accepted on: 21 October 2003.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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Submitted on: 25 September 2006.
Revised on: 06 November 2006.
Accepted on: 25 December 2006.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA