About Calvin Coolidge
Notes "Early Settlers Plymouth, Vermont", page 115. Calvin Coolidge settled on the farm given to him by his father in 1801 when he was twenty-one years of age. 
- Find A Grave Memorial# 43242471
- [S987] Book: Plymouth, Vermont History, Bryant, Blanche Brown & Baker, Gertrude Elaine, (1975, Springfield, Vermont, William L. Bryant Foundtion), page 115.
- The American Genealogist, (New Haven, Connecticut: D. L. Jacobus, 1937-), 1977, Vol. 53, Page 66, New England Historic Genealogical Society, Online Database
- thePeerage.com: A Genealogical Survey of the Peerage of Britain as Well as the Royal Families of Europe