Catechism of the Catholic Church §173 — excerpt
"Indeed, the Church, though scattered throughout the whole world, even to the ends of the earth, having received the faith from the apostles and their disciples.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: St. Irenaeus, Adv. haeres. I, 10, 1-2: PG 7/1, 549-552