Ante-Nicene Fathers: Introductory Note to the Epistles of Ignatius - American revision by A. Cleveland Coxe, of the original introductory notice, gives information on the genuine and spurious epistles, the shorter and longer Greek versions, and the discovery in 1842 of Syriac versions of three of the genuine epistles.
The Ignatian Epistles Entirely Spurious - E-text of 1886 "Reply to The Right Rev. Dr. Lightfoot" by W. D. Killen, Irish presbyterian, proposing that the epistles were third-century forgeries promoting the monoepiscopate system.