John Paul II, P. (1987). Unity in the work of service. National Conference of Catholic Bishops, United States Catholic Conferences.
Chicago-viite (17. p.)John Paul II, Pope. Unity in the Work of Service. Washington, D.C.: National Conference of Catholic Bishops, United States Catholic Conferences, 1987.
MLA-viite (8. p.)John Paul II, Pope. Unity in the Work of Service. National Conference of Catholic Bishops, United States Catholic Conferences, 1987.
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