Thilakarthne, N.S.; Weerakkody, W.J.S.K.; Wijesundara, D.S.A.(Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, 2005)
Karunarathne, M.M.K.; Weerakkody, W.J.S.K.; Wijesundara, D.S.A.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2006)