"Illinois Deaths and Stillbirths, 1916-1947," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:N3T4-KDZ : 8 March 2018), Jane Delong in entry for Frank Luther Heilig, 22 Nov 1928; Public Board of Health, Archives, Springfield; FHL microfilm 1,642,927.
"Illinois Deaths and Stillbirths, 1916-1947," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:N3Z7-8J4 : 8 March 2018), Anna Delonge in entry for Arthur D Heilig, 01 Nov 1930; Public Board of Health, Archives, Springfield; FHL microfilm 1,653,487.
"Illinois, Cook County Deaths, 1871-1998," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:Q2MD-8VL2 : 18 March 2018), Helien Delong in entry for Maybelle Joan, 02 Aug 1944; citing Chicago, Cook, Illinois, United States, source reference , record number , Cook County Courthouse, Chicago; FHL microfilm .