Nikahetiya, S.B.R.Gunawardena, A.T.M.Asmar, SamirWijeratne, C.M.Agrarian Research and Training Institute2014-07-182014-07-181977https://dl-harti.nsf.gov.lk//handle/1/2137v, 33p.Agricultural ExtensionSri LankaThe effectiveness of agricultural extension methodology