Liebenberg, J., L. du Toit-Prinsloo, G. Saayman, and V. Steenkamp. “Prevalence and Profile of Drugs and Alcohol in Fatally Injured Drivers in Pretoria, South Africa”. Social and Health Sciences, vol. 18, no. 1, 2020, pp. 61–80, https://unisapressjournals.co.za/index.php/SaHS/article/view/13182.