Fernando, B.K.N.S.; Jayaweera, B.P.A.; Ranaweera, B.; Edirisinghe, U.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)
Nawarathna, N.D.M.H.C.; Edirisinghe, U.; Ranaweera, B.; Jayaweera, B.P.A.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)