John XXIII, P. (1960). On the use of leisure time: Letter to Social Week of Italian Catholics, September 20, 1959. National Catholic Welfare Conference.
Chicago-Zitierstil (17. Ausg.)John XXIII, Pope. On the Use of Leisure Time: Letter to Social Week of Italian Catholics, September 20, 1959. Washington, D.C.: National Catholic Welfare Conference, 1960.
MLA-Zitierstil (8. Ausg.)John XXIII, Pope. On the Use of Leisure Time: Letter to Social Week of Italian Catholics, September 20, 1959. National Catholic Welfare Conference, 1960.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.