The History of Dubuque County, Iowa Containing A History of the County, its City, Towns, &c (Chicago: Western Historical Company, 1880), page 877; digital images, Google Books (https://books.google.com : accessed 2 December 2015
The Lowell Directory and Business Key (Lowell, Massachusetts: Oliver March, 1849), about page 6 and page 187, E G Shackford; digital images, My Heritage Library Edition (http://myheritagelibraryedition.com : accessed 28 January 2015
The Lowell Directory, Containing the City Record, Schools, Churches, Banks, Societuesm Etc., Names of the Citizens, (Lowell: Adams, Sampson, & Co, 1861), page 205, Elbridge G. Shackford; digital images, Ancestry.com (http://www.ancestry.com : accessed 2 December 2015).
Massachusetts, Massachusetts, Town and Vital Records, 1620-1988, , Elbridge G Shackford and Abby B Crockett, ; digital images, Ancestry.com (http://www.ancestry.com : accessed 2 December 2015); Town and City Clerks of Massachusetts. Massachusetts Vital and Town Records