Bluestein, M., S. Kelder, C. L. Perry, and A. Pérez. “Exploring Associations Between the Use of Alcohol and Marijuana With E-Cigarette Use in a U.S.A. Nationally Representative Sample of Young Adults”. International Journal of Health Sciences, vol. 13, no. 1, Dec. 2018, https://pub.qu.edu.sa/index.php/journal/article/view/3580.