Kostanso wa Perugia (alifariki Foligno, Umbria, Italia, karne ya 3 hivi) alikuwa askofu wa kwanza wa mji huo akajitahidi kuinjilisha na kusaidia maskini. Tangu zamani anaheshimiwa na Wakatoliki na Waorthodoksi kama mtakatifu mfiadini. Sikukuu yake inaadhimishwa kila mwaka tarehe 29 Januari. Watakatifu wa Agano la Kale Orodha ya Watakatifu Wakristo Orodha ya Watakatifu wa Afrika Orodha ya Watakatifu Wafransisko Martyrologium Romanum The Book of Saints: A dictionary of persons canonized or beatified by the Catholic Church. Benedictine Monks of St. Augustine Abbey, Ramsgate. NY: Thomas Y. Crowell, 1966. "A Reconstruction of Taddeo di Bartolo's Altarpiece for San Francesco al Prato, Perugia," by Gail E. Solberg. The Burlington Magazine, Vol. 134, No. 1075 (October 1992)p. 646–656. Constantius at Patron Saints Index 29 January saints at Saint Patrick's Church Archived 21 Desemba 2016 at the Wayback Machine. Umbria Best Gastronomy San Costanzo di Perugia