Mahendra, R.A.R.; Attanayaka, D.P.S.T.G.; Chandrasekharan, N.V.; Ranathunga, R.A.C.A.; Withanage, S.P.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2013)
Tennakoon, M.S.B.W.T.M.N.S.; Attanayaka, D.P.S.T.G.; Mahendra, R.A.R.(Faculty of Agriculture and Plantation Management,Wayamba University of Sri Lanka, Makandura, 2016)