Catholic Encyclopedia (1913)/Pope St. Adrian III
Adrian III, Saint, Pope, of Roman extraction, was elected in the beginning of the year 884, and died near Modena in the summer of the following year, while on his way to the diet summoned by Charles the Fat to determine the succession to the Empire. He was buried in the monastery of Nonantula, where his memory has ever since been held in local veneration. By decree of Pope Leo XIII the clergy of Rome and Modena celebrate his Mass and office ritu duplici on 7 September.
Liber Pontif. (ed. Duchesne), II, 225; Jaffé, Regesta RR. PP. (2d ed.), I. 426, 427, II, 705; Quattrini, Del cullo del papa Sant' Adriano III a Nonantola (Modena, 1889); Maini, Le più antiche memorie del culto a Sant' Adriano III papa (Modena, 1890); Civittà Cattolica (1890), VI. 575–577; Analecta Bolland., XIII, 61, 62; Watterich, Vitæ Rom. Pont., I. 650, 718; Artaud de Montor, Lives and Times of the Roman Pontiffs (tr. New York, 1867), I. 251.