Jayamaha, D.J.M.N.; Samarajeewa, P.K.; Attanayaka, D.P.S.T.G.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)
Siriwardhana, S.M.T.T.; Samarasinghe, W.L.G.; Gimhani, D.R.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2016)
Perera, J.K.C.G.K.; Ramanayake, S.M.S.D.; Attanayaka, D.P.S.T.G.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)