Why the Immaculate Conception?
Catholic Encyclopedia: Immaculate Conception (The Doctrine and Its Roots)
The Immaculate Conception of Our Lady December 8
Mary's Immaculate Conception: A Memorable Anniversary
Ineffabilis Deus: 8 December 1854 (Dogma of the Immaculate Conception)
Why do we believe in the Immaculate Conception?
John Paul II goes to Lourdes; reflections on the Immaculate Conception
Your Praises We Sing--on the Dogma of the Proclamation of the Immaculate Conception, Dec. 8th
Eastern Christianity and the Immaculate Conception (Q&A From EWTN)