Submitted on: 14 July 2008.
Revised on: 15 August 2008.
Accepted on: 11 September 2008.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
Submitted on: 19 July 2010.
Revised on: 12 September 2010.
Accepted on: 25 September 2010.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
Submitted on: 16 April 2013.
Revised on: 13 May 2013.
Accepted on: 24 May 2013.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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Submitted on: 28 September 2023.
Revised on: 19 December 2023.
Accepted on: 14 January 2024.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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Submitted on: 03 July 2018.
Revised on: 27 August 2018.
Accepted on: 10 October 2018.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
Submitted on: 18 March 2000.
Revised on: 23 April 2000.
Accepted on: 12 May 2000.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
Submitted on: 24 July 2003.
Revised on: 16 August 2003.
Accepted on: 27 September 2003.
___________________JOURNAL OF THE NATIONAL SCIENCE FOUNDATION OF SRI LANKA
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