00323nam a2200121Ia 4500008004100000100001700041245006300058260002800121300001200149650001100161650001900172650001000191220216s9999    xx            000 0 und d  aShearlaw P W 0aSurvey of commercial yields in relation to tapping systems  bPlanters Bulletinc1961  a117-138  aRubber  aTapping system  aYield