Timinkul, A., Phiwjinda, K. and Chaiut, W. (2018) “Comparison of Respiratory Muscle Strength between Native Lowlands and Native Highlands Populations in Chiang Rai”, Srinagarind Medical Journal, 33(3), pp. 235–240. available at: https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/122216 (accessed: 17 September 2026).