"Illinois, Cook County Deaths, 1871-1998," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:Q2MK-S5ZB : 18 March 2018), Ann in entry for Owen Lavin, 14 Dec 1939; citing Chicago, Cook, Illinois, United States, source reference , record number , Cook County Courthouse, Chicago; FHL microfilm .