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. Human Mortality Database (ICPSR 138) Wilmoth, John R.; Shkolnikov, Vladimir 2. Puerto Rico Census Project, 1910 (ICPSR 4343) Palloni, Alberto; Winsborough, Halliman H.; Scarano, Francisco 3. Puerto Rico Census Project, 1920 (ICPSR 4344) Palloni, Alberto; Winsborough, Halliman H.; Scarano, Francisco 4. Victoria Longitudinal Study (ICPSR 117) Dixon, Roger A.