1. Explaining recent increases in students' marijuana use: impacts of perceived risks and disapproval, 1976 through 1996.
2. , , . 2000. The relationship between teenage employment and crime in the NLSY97. Report to the Department of Labor.
3. Marijuana Legalization: Certainty, Impossibility, Both, or Neither?
4. , , , , , . 2004. The price and purity of illicit drugs: 1981 through the second quarter of 2003. Publication Number NCJ 207768, Office of National Drug Control Policy.