Chandrapathma, W.P.N.S.; Amarasinghe, N.J. De S.; Wickramasinghe, M.G.V.; Guruge, W.A.H.P.(Faculty of Science, University of Ruhuna, Matara, Sri Lanka, 2016-01-28)
Jayawardana, S. A. S.; Samarasekera, J. K. R. R.; Hettiarachchi, G. H. C. M.; Gooneratne, J.(Faculty of Science, University of Ruhuna, Matara, Sri Lanka, 2016-01-28)