Proceedings of the Malaysian Society of Soil Science Conference 2002 : Applications of Modern Tools in Agriculture: Perlis (Malaysia), 23-24 Apr 2002, p. 69-71
Proceedings 2007 Conference on Plantation Commodities: Visionary Agriculture: Malaysian Commodity Crops in 100 Years: Kuala Lumpur (Malaysia), 3-4 Jul 2007, p. 229-238
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