See this legally free ebook:

  • The Evidence for the Papacy: as Derived from the Holy Scriptures and from Primitive Antiquity, with an Introductory Epistle, by Colin Lindsay (London: Longmans, Green, & Co., 1870). Available at Internet Archive and Open Library.

On the Feast of Pope St. Victor I and Pope St. Innocent I in the Extraordinary Form of the Roman Rite. For more legally free ebooks, you may access the List of Free eBooks (Arranged by Title) and the List of Free eBooks (Grouped by Subject). Blessed be God in His angels and in His saints!