Perera, M.B.A.Humbel, R.2014-11-182014-11-181984Tea Quarterly53(1-2)pp.11-18https://dl.nsf.gov.lk/handle/1/13336AgriculturePlant densityActual surface areaSurveyed areaYieldComparative study of the relationship of tea yields and area variations due to slopes in hilly terrain using aerial photographs and survey mapsA