Rathnasekara, G.N.C.; Gajanayake, K.G.M.C.P.B.; Abeyagunawardene, C.D.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)
Muhsin, A.M.I.; Fernando, M.T.N.; Athauda, A.M.T.P.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)