John XXIII, P. (1960). On the use of leisure time: Letter to Social Week of Italian Catholics, September 20, 1959. National Catholic Welfare Conference.
Čikaški stil citiranja (17. izdanje)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 način citiranja (8. izdanje)John XXIII, Pope. On the Use of Leisure Time: Letter to Social Week of Italian Catholics, September 20, 1959. National Catholic Welfare Conference, 1960.
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