C. S, B. S, M. M, M. R. M, C. J, D. G. Prevalence of non-motor symptoms in Parkinson’s disease. Int J Res Med Sci [Internet]. 2019 Apr. 26 [cited 2025 Oct. 12];7(5):1459-64. Available from: https://www.msjonline.org/index.php/ijrms/article/view/6149