Baltimore Catechism

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Biblical Evidence for Catholicism by Dave Armstrong

Canons and Decrees of the Council of Trent

Calvinism and Catholicism (A Catholic perspective of the five points of Calvinism)

Catechism of the Catholic Church

Companion to the Catechism of the Catholic Church

Catechism of Trent

Catholic Dictionary

Catholic Encyclopedia Online
A highly recommended and reliable source for researching Catholicism.

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Haydock's Catholic Bible Commentary

Master Catechism comparing 5 Historic Catechisms: The Catechetical Instructions of St. Thomas Aquinas (1273), Catechism of the Council of Trent (1566), Baltimore Catechism (1891), Catechism of St. Pius X, Catechism of the Catholic Church (1992).

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Summa Theologica of St. Thomas Aquinas

The Sources of Catholic Dogma by Denzinger

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