00423nam a2200121Ia 4500008004100000100001700041245011100058260006400169300001000233650002200243650001400265650002200279220216s9999    xx            000 0 und d  aYogaratnam N 0aUrea as a source of nitrogen for rubber plantations in Sri Lanka. 1. A review and preliminary observations  bJournal of the Rubber Research Institute of Sri Lankac1981  a13-19  aRubber plantation  aSri Lanka  aUrea fetilization