Harshana, W.H.I.; Nugawela, R.C.W.M.R.A.; Attanayake, D.P.S.T.G.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2016)
Pathirana, A.P.C.S.; Sumanasena, H.A.; Fernandopulle, M.N.D.; Amarasinghe, K.G.A.P.K.; Priyadarshani, K.D.N.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2013)