i. "Marriage register for the parish of Calverton in Nottinghamshire covering 1837-1900," transciption database, Society of Genealogists; Page accessed 13 Jan 2020), Entry for William Blacknell & Harriett Worthington.; [Source Record]; Certainty Primary Evidence
ii. Public Record Office, "Census Returns of England and Wales, 1861"; Page PRO RG9/2444 f12 p14; [Source Record]; Certainty Primary Evidence
iii. Public Record Office, "Census Returns of England and Wales, 1871"; Page RG10 3494 p18; [Source Record]; Certainty Primary Evidence