Study Search Results Your query returned 4 results. Series results are grouped under the most relevant study. You can ungroup series results. Use the search box below to revise your search, or start a new search. 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. ABC News Hurricane Katrina Anniversary Poll, August 2006 (ICPSR 4664) ABC News 2. Negro Political Attitudes, 1964 (ICPSR 7002) Marx, Gary T. 3. Negro Political Participation Study, 1961-1962 (ICPSR 7255) Matthews, Donald; Prothro, James 4. Union Army Recruits in Black Regiments in the United States, 1862-1865 (ICPSR 9426) Metzer, Jacob; Margo, Robert A.