Kwon, Young-Gyu, and Man-Kyu Choi. “Spatial Analysis of the Relationship Between Out-of-Pocket Expenditure and Socioeconomic Status in South Korea”. Geospatial Health 18, no. 1 (May 25, 2023). Accessed May 17, 2024. https://www.geospatialhealth.net/gh/article/view/1175.