Search Results Use the search box below to revise your search, or start a new search. Studies (2) Variables Publications Your query returned 2 studies. Series results are grouped under the most relevant study. Ungroup series results to view all results. Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. 1. Negro Political Participation Study, 1961-1962 (ICPSR 7255) Matthews, Donald; Prothro, James 2. Southern Primary and General Election Data, 1946-1972 (ICPSR 72) Bartley, Numan V.; Graham, Hugh D.