00303nam a2200109Ia 4500008004100000100001500041245005800056260002800114300001200142650001700154650002200171220216s9999    xx            000 0 und d  aDaumas M G 0aChanging from conventional to crumb rubber production  bPlanters Bulletinc1969  a313-317  aCrumb rubber  aRubber production