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Title - Elmer--Elmore genealogy : records of the descendants of Edward Elmer of Braintree, Eng. and Hartford, Conn., through his son Edward, 1632-1899
https://www.familysearch.org/eng/library/fhlc/click on "TITLE SEARCH"
Next window - fill in "Elmer-Elmore"
the book by Johnson is the top one, (there are three, I have not looked at the others)
Author - Johnson, William W.
Description - Edward Elmer (ca.1619-1676) immigrated from England to Braintree, Massachusetts in 1632, and later moved to Hartford, Connecticut. Descendants and relatives lived in New England, New York, Ohio, Iowa, Wisconsin and elsewhere.