Proceedings of The National Seminar on Mechanization in Oil Palm Plantation: Towards Improving Productivity Through Mechanization: Selangor (Malaysia), 30 Jun-1 Jul 1998, p. 3-15
Proceedings of the National Oil Palm Planters Conference 2002 : Strategy and Goals Towards Reinforcement for Oil Palm Planters Sector, 31 October-1 November 2002: Putrajaya (Malaysia),p. 87-92