Catechism of the Catholic Church §750 — excerpt
To believe that the Church is "holy" and "catholic," and that she is "one" and "apostolic" (as the Nicene Creed adds), is inseparable from belief in God, the Father, the Son, and the Holy Spirit.
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: Roman Catechism I, 10, 22