Roman Catechism 18.129

Chapter 18 — Part II: The Sacraments — The Holy Eucharist

Section 129. Threefold Manner Of Communicating — That the faithful may learn to be zealous for the better gifts, they must be shown who can obtain these abundant fruits from the Holy Eucharist, must be reminded that there is not only one way of communicating. Wisely and rightly, then, did our predecessors in the faith, as we read in the Council of Trent, distinguish three ways of receiving this Sacrament.