Aphisitphinyo, S., S. Arunpongpaisal, S. Tiamkoa, and P. Paholpak. “Prevalence of Major Depressive Disorder in Parkinson’s Disease at Srinagarind Hospital”. Journal of the Psychiatric Association of Thailand, vol. 62, no. 2, July 2017, pp. 167-76, https://he01.tci-thaijo.org/index.php/JPAT/article/view/92335.