Kaushalya, M.G.M.T.; Disaanayake, D.M.P.S.; Weerakkody, W.J.S.K.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2016)
Abeywardana, B.G.H.; Jayasundera, S.H.; Kumara, N.K.D.C.P.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)