"New York, New York City Births, 1846-1909," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:2W3F-R3L : 20 March 2015), Mary Jane Cook Hopper in entry for William Hopper, 07 Nov 1888; citing Manhattan, New York, New York, United States, reference cn 1142 New York Municipal Archives, New York; FHL microfilm 1,323,485.
Citing this Record "New York, New York City Municipal Deaths, 1795-1949," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:2W8B-5G1 : 20 March 2015), Mary Jane Hopper in entry for William Hopper, 23 Aug 1889; citing Death, Manhattan, New York, New York, United States, New York Municipal Archives, New York; FHL microfilm 1,322,671.
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