Sampath, H.A.K.K.; Gajanayake, K.G.M.C.P.B.; Raveendran, K.; Karunarathne, S.B.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)
Karunarathne, S.B.; Weerakkody, W.J.S.K.; Rajapakshe, H.A.; Adikari, A.M.K.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)