Study Search Results Your query returned 1 results. Results per page: 25 50 100 Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. Most Downloaded (?) Study Title/Investigator 1. Estimating the Elasticities of Demand for Cocaine and Heroin with Data from 21 Cities from the Drug Use Forecasting (DUF) Program, 1987-1991 (ICPSR 6567) Caulkins, Jonathan P.