Chandrasena, T.G.A.N.; Premaratna, R.; de Alwis, A.C.; de Silva, L.D.R.; Morel, R.P.; de Silva, N.R.(SEAMEO Regional Tropical Medicine and Public Health Project, 2004)
Premaratna, R.; Gunatilake, A.K.E.; de Silva, N.R.; Tilakaratne, Y.; Fonseka, M.M.D.; de Silva, H.J.(SEAMEO Regional Tropical Medicine and Public Health Project, 2001)