Study Search Results Your query returned 4 results. Series results are grouped under the most relevant study. You can ungroup series 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. Negro Political Participation Study, 1961-1962 (ICPSR 7255) Matthews, Donald; Prothro, James 2. New Orleans Slave Sale Sample, 1804-1862 (ICPSR 7423) Fogel, Robert W.; Engerman, Stanley L. 3. Union Army Recruits in Black Regiments in the United States, 1862-1865 (ICPSR 9426) Metzer, Jacob; Margo, Robert A. 4. Union Army Recruits in Black Regiments in the United States, 1862-1865: [Instructional Materials] (ICPSR 3466) Oberly, James W.