รู้สุข ก., วงศ์เหลา เ. . and ไชยณรงค์ ป. . . (2021) “The Development of Mathematics Learning Packages through Inquiry Method on the Ratios of Trigonometry for Mathayom Suksa 4 students”, Ubon Ratchathani Journal of Research and Evaluation, 4(1), pp. 79–87. available at: https://so06.tci-thaijo.org/index.php/ubonreseva/article/view/250969 (accessed: 12 April 2025).