William Waller Hening, editor, The Statutes at Large; Being a Collection of all the Laws of Virginia, from the First Session of the Legislature in the year 1619, 13 vols. (Richmond: Samuel Pleasants, Junior, 1809), vol. 1, page 224, in 1634 Charles River Shire created as one of the original 8 shires, digital images, Internet Archive (https://archive.org : 2 April 2019).
William Waller Hening, editor, The Statutes at Large; Being a Collection of all the Laws of Virginia, from the First Session of the Legislature in the year 1619, 13 vols. (Richmond: Samuel Pleasants, Junior, 1809), vol. 1, page 249, "Act XIII," 2 March 1642/3, "Charles River county shall be distinguished by this name (the County of York)", digital images, Internet Archive (https://archive.org : 2 April 2019).