William Penn (1857). “Primitive Christianity revived in the faith and practice of the people called Quakers: Written in testimony to the present dispensation of God through them to the world that prejudices may be removed, the simple informed, the well-inclined encouraged, and the truth, and its innocent friends rightly represented”
Thomas Clarkson, William Penn (1827). “Memoirs of the private and public life of William Penn: who settled the state of Pennsylvania, and founded the city of Philadelphia”, p.116
William Penn (1726). “A Collection of the Works of William Penn: To which is Prefixed a Journal of His Life, with Many Original Letters and Papers Not Before Published”, p.849