https://imslp.org/wiki/Miserere_(Allegri,_Gregorio)
Miserere (Allegri, Gregorio) - IMSLP
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https://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/allegri-gregorio
Allegri, Gregorio | Encyclopedia.com
ALLEGRI, GREGORIO Priest, composer of the Roman baroque; b. Rome, 1582; d. Rome, Feb. 17, 1652. As a boy he sang under G. B. Nanino at S. Luigi dei Francesi...
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