Rathnayake, R.M.S.J.; Dissanayake, D.M.P.S.; Weerakkody, W.J.S.K.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2013)
Jayathilake, T.S.; Dissanayake, D.M.P.S.; Weerakkody, W.J.S.K.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2016)