Excerpts from Sacrosanctum Concillium

The Vatican Council II document on the reform of the Roman liturgy, issued on December 4, 1963.

Sacrosanctum Concilium, no. 4

"Lastly, in faithful obedience to tradition, the sacred Council declares that holy Mother Church holds all lawfully acknowledged rites to be of equal right and dignity; that she wishes to preserve them in the future and to foster them in every way."

Sacrosanctum Concilium, no. 36

[...] the use of the Latin language is to be preserved in the Latin rites."

Sacrosanctum Concilium, no. 116

"The Church acknowledges Gregorian chant as specially suited to the Roman liturgy: therefore, other things being equal, it should be given pride of place in liturgical services."

The complete document can be viewed here.