A massive database for choral music where you can find various historical arrangements of the Lourdes themes.

For those seeking to perform it, reliable partitions can be found in Catholic hymnals such as the Cantiques de Lourdes (Edition des Sanctuaires) or through online sheet music databases like IMSLP (under "Lourdes Mass" or "Messe de Lourdes" by various anonymous or lesser-known composers).

What an intriguing combination of words! After some creative digging, I've come up with a story that brings together "Sanctus," "de Lourdes," and "partition top."