1. ASTM D2227–90: Standard specification for natural rubber technical grades, 1990.
2. Rubber Research Institute of Malaysia. Revisions to the Standard Malaysian Rubber Scheme. SMR Bulletin No. 11, 1991.
3. “The Synthetic Rubber Manual,” 11th ed. International Institute of Synthetic Rubber Producers, Houston, TX, 1989.
4. Rubber Demand Is Expected To Grow after 1991