Herman, AA, DJ Stein, S Seedat, SG Heeringa, H Moomal, and DR Williams. 2010. “The South African Stress and Health (SASH) Study: 12- Month and Lifetime Prevalence of Common Mental Disorders”. South African Medical Journal 99 (5). https://www.ajol.info/index.php/samj/article/view/50764.