Wijegunawardana, N.D.A.D.; Gunawardene, Y.I.N.S.; Manamperi, A.; Hapuarachchi, H.A.C.; Bandara, K.B.A.T.; Abeyewickreme, W.(Sri Lanka Association for the Advancement of Science, 2008)
Gunawardene, Y.I.N.S.; Wijesundera, W.S.; Karunanayake, E.H.; Chandrasekharan, N.V.; Jayasekara, N.; Siridewa, K.(SEAMEO Regional Tropical Medicine and Public Health Project, 1999)