In 1963 Paul VI established the Consilium which was tasked with the job of carrying out the liturgical reform mandated by Vatican II. Consilium formulated a new Order of Mass which Paul VI promulgated on April 3, 1969.
And so it was that close to 12 cardinals had agreed to sign the study including Arcadio Cardinal Larraona, former head of the Sacred Congregation of Rites. After examining the Critical Study, Cardinal Ottaviani signed the cover letter on Sept. 13 1969.
Antonio Cardinal Bacci was a famous Latinist and during this time served on the Vatican Congregations for Religious, Causes of Saints, and Catholic Education, and was one of the most outstanding scholars on Latin in the Curia having published the Lexicon Eorum Vocabulorum Quae Difficilius Latine Redduntur, a dictionary of modern terms in Latin and a standard reference for writers of Latin, especially in the Vatican, continued his support along with Ottaviani. In 1967 Cardinal Bacci had written a complimentary preface to a book which accused the liturgical reform of abandoning the Council of Trent in favour of novel theologies, and that Cardinal Lercaro, the head of Consilium, was “Luther resurrected.” Cardinal Bacci signed the letter on September 28, and, on September 29, the Study and the covering letter were presented to Paul VI. Almost 2 years later, on Jan. 20, 1971, Antonio Cardinal Bacci died at 84.