Mackenzie, J., & Joly, J. R. (1690). Dr. Walker's invisible champion foyl'd: or, An appendix to the late Narrative of the siege of Derry: Wherein all the arguments offered in a late pamphlet [by J.W. Clark?] to prove it a false libel, are examin'd and refuted. printed for the author, and sold by the booksellers of London.

Mackenzie, John, and Jaspar Robert Joly. Dr. Walker's Invisible Champion Foyl'd: Or, An Appendix to the Late Narrative of the Siege of Derry: Wherein All the Arguments Offered in a Late Pamphlet [by J.W. Clark?] to Prove It a False Libel, Are Examin'd and Refuted. printed for the author, and sold by the booksellers of London, 1690.