Dharmaratne, H.R.W.Herath, H.M.T.B.Weerawardhena, W.D.P.P.2016-06-202016-06-201994Proceedings of the 50th Annual Sessions of the Sri Lanka Association for the Advancement of Science:p.228https://dl.nsf.gov.lk/handle/1/23313ChemistryARG/93/C/001FR 1098