Columbia subject headings:
Catholic Church--Liturgy--History--20th century--Sources.
Liturgical reform--History--20th century--Sources.
Vatican Council (2nd : 1962-1965 : Basilica di San Pietro in Vaticano). Constitutio de sacra liturgia.
Harvard subject headings:
Catholic Church--Liturgy--History--20th century--Sources.
Vatican Council (2nd : 1962-1965 : Basilica di San Pietro in Vaticano). Constitutio de sacra liturgia.
Princeton subject headings: