Rubber-tapping experiments
Petch, T.
Rubber-tapping experiments Two cuts versus one cut - Colombo 1918 - 1-6 p. - Experiment Ceylon Department of Agriculture. Bulletin No. 41 .
Rubber-tapping experiments Two cuts versus one cut - Colombo 1918 - 1-6 p. - Experiment Ceylon Department of Agriculture. Bulletin No. 41 .