His The three greatest prayers, 1987 CIP introd. (Reginald of Piperno)
LC manual cat. (hdg.: Reginaldus, de Piperno, 13th century)
New Cath. encyc. (Reginald of Piperno, d. Anagni 1290; Dominican friar who became secretary, confessor and friend of Thomas Aquinas from 1259; he succeeeded Thomas in the chair of theology at Naples, and completed several of his unfinished works)
Oxford dict. of the Christian church, 1958 (Reginald of Piperno, ca. 1230-ca. 1290, Dominican friar, confessor and secretary to Thomas Aquinas; he took notes of Thomas's lectures and finished the Summa theologica after Thomas's death)