John XXIII, P. (1965). Encyclicals of Pope John XXIII. National Catholic Welfare Conference.
Chicago-viite (17. p.)John XXIII, Pope. Encyclicals of Pope John XXIII. Washington: National Catholic Welfare Conference, 1965.
MLA-viite (8. p.)John XXIII, Pope. Encyclicals of Pope John XXIII. National Catholic Welfare Conference, 1965.
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