Puapermpoonsiri, Pichai, and Ronnalin Eua-apithorn. “Comparison of Nasal Mucociliary Clearance Time with Saccharin Clearance Test of Volunteers in Bangkok and Chiangrai Province: a Pilot Study”. Vajira Medical Journal : Journal of Urban Medicine 54, no. 3 (September 29, 2011): 261–265. accessed April 22, 2026. https://he02.tci-thaijo.org/index.php/VMED/article/view/455.