Proceedings of the Malaysian Society of Soil Science Conference 2002 : Applications of Modern Tools in Agriculture: Perlis (Malaysia), 23-24 Apr 2002, p. 167-170
Proceedings of the Workshop on Phosphate Sources for Acid Soils in the Humid Tropics of Asia, Rubber Research Inst. of Malaysia, Kuala Lumpur (Malaysia): Kuala Lumpur (Malaysia), 6-7 Nov 1990, p. 59-71