Kosgahakumbura, K.N.M.A.S.K.; Bogahawatta, C.N.L.; Wickramasinghe, M.G.V.; Wegiriya, H.C.E.(Faculty of Science, University of Ruhuna, Matara, Sri Lanka, 2009-12-23)
Kishanthi, J.K.A.; Bogahawatta, C.N.L.; Wegiriya, H.C.E.; Wickramasinghe, M.G.V.; Dinusha, R.W.V.G.G.(Faculty of Science, University of Ruhuna, Matara, Sri Lanka, 2009-12-23)