"Illinois, Cook County, Birth Certificates, 1871-1940," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:QGCF-H9BN : 18 March 2018), Donald Cortez Cornelius, 27 Sep 1936; Chicago, Cook, Illinois, United States, reference/certificate 35232, Cook County Clerk, Cook County Courthouse, Chicago; FHL microfilm .
"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KWTL-TYX : accessed 5 May 2018), Donald Cornelius in household of Carter Cornelius, Ward 3, Chicago, Chicago City, Cook, Illinois, United States; citing enumeration district (ED) 103-131, sheet 10A, line 26, family 235, Sixteenth Census of the United States, 1940, NARA digital publication T627. Records of the Bureau of the Census, 1790 - 2007, RG 29. Washington, D.C.: National Archives and Records Administration, 2012, roll 925.
"United States, GenealogyBank Obituaries, 1980-2014," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:QVP5-S7NM : accessed 5 May 2018), Donald Cortez Cornelius, California, United States, 01 Feb 2012; from "Recent Newspaper Obituaries (1977 - Today)," database, GenealogyBank.com (http://www.genealogybank.com : 2014); citing Whittier Daily News, The, born-digital text.