"Massachusetts Births and Christenings, 1639-1915," database, FamilySearch (https://familysearch.org/pal:/MM9.1.1/FZ86-Y8Y : 10 February 2018), Mary Darby, 30 Jun 1806; citing LEOMINSTER,WORCESTER,MASSACHUSETTS, ; FHL microfilm 0874029 IT 2.
"Massachusetts Births and Christenings, 1639-1915," database, FamilySearch (https://familysearch.org/pal:/MM9.1.1/VQD9-SH3 : 10 February 2018), Mary R. Derby, 30 Jun 1806; citing WRENTHAM,NORFOLK,MASSACHUSETTS, ; FHL microfilm 0253249 V. 1.
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MDS4-S9M : 12 April 2016), Mary R Derby, Weymouth, Norfolk, Massachusetts, United States; citing family 307, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).
"Massachusetts Deaths, 1841-1915," database with images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/N7RR-5JT : 10 March 2018), Mary R. Derby, 09 Jun 1891; citing Norfolk, Massachusetts, v 419 p 459, State Archives, Boston; FHL microfilm 961,504.