Srisongkham, S. and Photong, C. (2020) “Ion Balance Measuring and Recording System for Air Ionizers: doi: 10.14456/mijet.2021.6”, Engineering Access. Mahasakham, Thailand, 7(1), pp. 36–42. available at: https://ph02.tci-thaijo.org/index.php/mijet/article/view/10.14456.mijet.2021.6 (accessed: 27 August 2026).