Search Results Use the search box below to revise your search, or start a new search. Studies (1) Variables Publications Your query returned 1 studies. Series results are grouped under the most relevant study. Ungroup series results to view all 1 results. Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. 1. Deterrent Effect of Curfew Enforcement: Operation Nightwatch in St. Louis, 2003-2005 (ICPSR 4302) Urban, Lynn S.