Trends in marijuana and other illicit drug use among college students: Results from 4 Harvard School of Public Health college alcohol study surveys: 1993-2001

Mohler-Kuo, M. Lee, J.E., & Wechsler (2003). Trends in marijuana and other illicit drug use among college students: Results from 4 Harvard School of Public Health college alcohol study surveys: 1993-2001. Journal of American College Health, 52(1).