Proceedings of the Soils Science Conference of Malaysia 2008: Sustaining Soil Ecosystems with Emphasis on Coastal Soils: Perak (Malaysia), 15-17 Apr 2008, p. 26-30
Proceedings of the Malaysian Society of Soil Science Conference 2002 : Applications of Modern Tools in Agriculture: Perlis (Malaysia), 23-24 Apr 2002, p. 116-119
Proceedings of The National Seminar on Mechanization in Oil Palm Plantation: Towards Improving Productivity Through Mechanization: Selangor (Malaysia), 30 Jun-1 Jul 1998, p. 119-126