Perera, B.S.P.S.S.; Fernandopulle, M.N.D.; Sherath, C.S.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)
Nayakarathna, N.M.S.K.; Athauda, A.M.T.P.; Abeynayake, N.R.; Anjalee, G.H.I.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2013)