113 Liturgical worship is given a more noble form when the divine offices are celebrated solemnly in song, with the assistance of sacred ministers and the active participation of the people. As regards the language to be used, the provisions of Art. 36 are to be observed; for the Mass, Art. 54; for the sacraments, Art. 63; for the divine office. Art. 101.
Source: Sacrosanctum Concilium (Vatican.va)