| Sources |
- [S20145] 1910 census, Massachusetts, Essex county, Year: 1910; Census Place: Gloucester Ward 4, Essex, Massachusetts; Roll: T624_581; Page: 4B; Enumeration District: 0293 (Reliability: 3).
- [S53724] Birth record, Massachusetts, Name: John Sumner Dennen Gender: Male Birth Date: 26 Feb 1904 Birth Place: Gloucester, Massachusetts, USA Father: James A Dennen Mother: Emma M Parsons (Reliability: 3).
- [S53723] Death index, Massachusetts, Name: John S Dennen Certificate: 049083 Death Place: Barnstable Death Date: 8 Nov 1980 Birth Place: Massachusetts Birth Date: 26 Feb 1904 (Reliability: 3).
- [S11437] 1900 census, Massachusetts, Essex county, Year: 1900; Census Place: Gloucester Ward 8, Essex, Massachusetts; Roll: 641; Page: 1; Enumeration District: 0287 (Reliability: 3).
- [S39740] 1930 census, Massachusetts, Suffolk county, Year: 1930; Census Place: Boston, Suffolk, Massachusetts; Page: 11B; Enumeration District: 0240 (Reliability: 3).
|