Pimda, P., N. Chaiear, K. Yimtae, J. Khiewyoo, P. Thanawiratananit, and N. Krusun. “Incidence of Industrial Employees Having Standard Threshold Shifts; A Study of the Existing Audiograms”. Srinagarind Medical Journal, vol. 31, no. 3, June 2016, pp. 287-92, https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/58475.