Y. P. Chu, Roszalli Hj. Mohd, and Y. T. Chong. “STRENGTH OF PLYWOOD-WEB BOX BEAM”. Journal of Tropical Forest Science (JTFS), vol. 5, no. 4, June 1993, pp. 492-11, https://jtfs.frim.gov.my/jtfs/article/view/1966.