Thammasaranyakun, Nuppharet (2010) Development of an instructional process using Sternberg's four step model and heuristics concept to enhance mathematical reasoning and problem-solving abilities of sixth grade students. In: Lifelong Learning International Conference 2010 (3LInC’10), 10 - 12 November 2010, Seri Pacific Hotel, Kuala Lumpur, Malaysia. (Unpublished)