John Paul II, P. (1988). On the occasion of the Marian year: Letter, May 22, 1988. Washington, D.C..
Chicago-viite (17. p.)John Paul II, Pope. On the Occasion of the Marian Year: Letter, May 22, 1988. Washington, D.C., 1988.
MLA-viite (8. p.)John Paul II, Pope. On the Occasion of the Marian Year: Letter, May 22, 1988. Washington, D.C., 1988.
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