See this online text:
- Sacred Music, Vol. 128, No. 4 (Winter 2001). Published by the Church Music Association of America. Includes the articles: “The Easter Triduum in Milan”, by Vincent A. Lenti; “The Mozarabic Chant Books of Cisneros”, by Dr. Angel Fernandez Collado; and “Reflections on the Liturgical Reform”, by Professor Roberto de Mattei. Available in pdf format (on this page) at Musica Sacra.

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“Not every kind of music can have a place in Christian worship. It has its standards, and that standard is the Logos. If we want to know whom we are dealing with, the Holy Spirit or the unholy spirit, we have to remember that it is the Holy Spirit who moves us to say, “Jesus is Lord” (1 Cor 12:3). The Holy Spirit leads us to the Logos, and he leads us to a music that serves the Logos as a sign of the sursum corda, the lifting up of the human heart. Does it integrate man by drawing him to what is above, or does it cause his disintegration into formless intoxication or mere sensuality? That is the criterion for a music in harmony with logos…” (Joseph Ratzinger / Pope Benedict XVI, as quoted in Catholic Champion)