Perry CL, Creamer MR, Chaffee BW, Unger JB, Sutfin EL, Kong G, Shang C, Clendennen SL, Krishnan-Sarin S, Pentz MA. Research on Youth and Young Adult Tobacco Use, 2013-2018, From the Food and Drug Administration-National Institutes of Health Tobacco Centers of Regulatory Science. Nicotine Tob Res. 2020 06 12; 22(7):1063-1076.