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William Brennan - line 42
Source - Year: 1900; Census Place: Waterloo, Black Hawk, Iowa; Roll: T623_418; Page: 20A; Enumeration District: 22
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William Brennan - line 20
Source - Year: 1910; Census Place: Waterloo Ward 4, Black Hawk, Iowa; Roll: T624_392; Page: 16A; Enumeration District: 0026; Image: 911; FHL Number: 1374405.
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Source - Year: 1915; Iowa State Census Collection, 1836-1925; Census Place: Waterloo, Black Hawk, Iowa; Roll: IA1915_35; Image: 3406
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William Brennan - line 24
Source - Year: 1920; Census Place: Waterloo Ward 4, Black Hawk, Iowa; Roll: T625_478; Page: 8A; Enumeration District: 30; Image: 1031.
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William Brennan - line 13
Source - Year: 1930; Census Place: Los Angeles, Los Angeles, California; Roll: 132; Page: 8A; Enumeration District: 11; Image: 516.0.
BRENNAN, William Edward passed away March 4, loving husband of Mary Arlyne Brennan, brother of Raphael J. Brennan, uncle of Raphael J. Brennan Jr.
Rosary 8:30 p.m. Monday in St. Jerome Church, Westchester. Requiem Mass 9 a.m. Tuesday at above church. Interment Holy Cross Cemetery. McCormick Mortuary, Westchester, directors.
Source - Los Angeles Times - Mar 5, 1967