"Iowa, County Marriages, 1838-1934," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:XJHL-DVG : 3 November 2017), John C. Mccallister and Ossie V. Martin, 16 Oct 1907, Marengo, Iowa, Iowa, United States; citing reference p516 Lic. 99, county courthouses, Iowa; FHL microfilm 988,206.
"United States Census, 1930," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:XMJJ-1RJ : accessed 20 August 2019), Ocie V Mcallister in household of John C Mcallister, Troy, Iowa, Iowa, United States; citing enumeration district (ED) ED 22, sheet 5B, line 56, family 107, NARA microfilm publication T626 (Washington D.C.: National Archives and Records Administration, 2002), roll 660; FHL microfilm 2,340,395.
Find A Grave, database and images (https://www.findagrave.com : accessed 19 August 2019), memorial page for Ocie Vay Martin McCallister (6 Dec 1888–18 Nov 1953), Find A Grave Memorial no. 52527248, citing Pilot Grove Cemetery, Williamsburg, Iowa County, Iowa, USA ; Maintained by Dott (contributor 47258609) .