Pushpakumari, O.P.G.; Siriwardhane, K.P.D.; Rathnayake, R.H.M.K.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)
Kumarasinghe, W.M.; Perera, S.A.C.N.; Gunasekara, T.M.C.P.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)