John Paul II, P. (1987). On the twelfth centenary of the second council of Nicaea: Duodecimum saeculum : apostolic letter, December 4, 1987. Washington, D.C..
Chicago Style aipamenaJohn Paul II, Pope. On the Twelfth Centenary of the Second Council of Nicaea: Duodecimum Saeculum : Apostolic Letter, December 4, 1987. Washington, D.C., 1987.
MLA aipamenaJohn Paul II, Pope. On the Twelfth Centenary of the Second Council of Nicaea: Duodecimum Saeculum : Apostolic Letter, December 4, 1987. Washington, D.C., 1987.
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