Dissanayake, D.M.A.P.Wickramasinghe, D.N.P.Puhambugoda, P.A.C.R.Munasinghe, R.2014-07-082014-07-082000Journal of the National Institute of Plantation of Management, 16(2):p.56-63https://dl-rri.nsf.gov.lk//handle/1/2340Article