Promsak Sa-nguanthammarong. (1999) A study of abrasion resistance of silica-filled natural rubber and its improvement. Mahidol University,:ม.ป.ท.Promsak Sa-nguanthammarong. 1999. A study of abrasion resistance of silica-filled natural rubber and its improvement. ม.ป.ท.:Mahidol University,;Promsak Sa-nguanthammarong. A study of abrasion resistance of silica-filled natural rubber and its improvement. ม.ป.ท.:Mahidol University, 1999. Print.