- [S82] Sheffield Parish Baptisms, Sheffield & District Family History Society, (FindMyPast.com), index entry for William Richard Parkin (1841), 4 May 2016.
- [S33] 1851 England Census, The National Archives of the UK, (Public Record Office), Ashton Under Lyne parish, Lancashire, England. p. 20, John Parkin household, citing PRO HO 107/2233, 22 Sep 2015.
- [S32] Castle Garden Immigration Records, castlegarden.org (Reliability: 2), 22 Aug 2010.
- [S11] 1880 United States Federal Census, (National Archives and Records Administration), T9., roll 0780. Essex County, New Jersey. East Orange township, ED 99, p. 520-B, dwelling 222, family 260, William R. Parkin household (Reliability: 3), 22 Aug 2010.
- [S17] Records of Births, Marriages, and Deaths of New Jersey, 1848-1900, New Jersey State Library, (The Genealogical Society of Utah: Salt Lake City, Utah; 1969), Film Number: 589831; Reference Number: Vol 10; (Reliability: 1), 22 Aug 2010.