Priyadarshane, W.M.C.; 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)
Karunarathne, M.M.K.; Weerakkody, W.J.S.K.; Wijesundara, D.S.A.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)