De Silva, L.B.Herath, W.H.M.W.Navaratne, M.Ahmed, V.U.Sultana, V.2016-06-202016-06-201987Proceedings of the 43rd Annual Sessions of the Sri Lanka Association for the Advancement of Science:p.234https://dl.nsf.gov.lk/handle/1/23292ChemistryARG/84/C/006