Kungpisdan, N., Suravanit, R., Prukwiwat, W., Prukwarun, S. and Ranlee, A. (2006) “Development of Technology in Fertilizer Utilization to Increase Yield of Rubber  ”, Thai Agricultural Research Journal, 24(2), p. 112. doi: 10.14456/thaidoa-agres.2006.9.