Saying "Gregorian chants are…" as opposed to "Gregorian chant is…" strangely reminds me of boomers referring to social media as "the Twitters", "the Youtubes", etc., but in a weirdly reversed way.
The books they are using came (largely) from Milwaukee--or more specifically, from St John Vianney parish in a western suburb. They were purchased for that church's choir in the mid-to-late 1950's. Fast forward about 60 years....they were possessed by the EF choir, but un-used, as the EF choir used Solesmes edition, and those are Vatican edition.
Fr. Robert Skeris secured and transported them to Nebraska.
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