I was going to cite Aristotle's Advent Propers in an upcoming diocesan workshop devoted to Advent & Christmas music, but have found to my dismay that both CCW and the CMAA have dropped the links to this cool work.
I'm not sure if you are looking for Aristotle's Choral Graduale Simplex, but if you do, you can find his propers here. The links on the CMAA website are dead and need to be updated...
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