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Catholic Encyclopedia - http://www.newadvent.org/cathen/14032a.htm
Pope St. Sixtus III, also spelled Xystus, d. 440. |
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Popes Through the Ages - http://www.cfpeople.org/Books/Pope/POPEp44.htm
Account of the pontificate of St. Sixtus III, from the book by Joseph Brusher. |
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The Ecole Glossary - http://www2.evansville.edu/ecoleweb/glossary/sixtusiii.html
Brief profile of Pope St. Sixtus III mentions that he founded the first known monastery in Rome. |