Hippolytus, Antipope, approximately 170-235 or 236

found: Hanssens, Jean Michel. La liturgie d'Hippolyte, 1965:title page (Hippolyte)

found: Holweck, F. G. (Frederick George). Biographical dictionary of the saints, 1924(Hippolytus; martyr, bishop and ecclesiastical writer, called Pope of Rome by the Greeks and Bishop of Portus Romanus by others; the Catholic Church venerates him as Bishop of Porto Romano; died 235)

found: Book of the saints, 1966(Hippolytus, Concordia; died ca. 236; Hippolytus of Porto and Hippolytus of Rome are actually the same individual, though often presented as two different men)

found: New Catholic encyclopedia. Second edition, 2003:volume 6, page 858 (Hippolytus of Rome, St.; ecclesiastical author, presbyter, antipope, and martyr; born circa 170; died 235 or 236 in Sardinia. The identity, life, and writings of Hippolytus continue to pose challenges to scholars. Probably of Eastern extraction, he became a member of the Roman clergy and distinguished himself as the foremost writer of the Roman church in the third century. He opposed Pope Callistus I and was elected antipope in 217. He reconciled with Callistus's successor Pontian while both he and Pontian were in exile in Sardinia, and resigned as antipope. He and Pontian both died in Sardinia)

found: nuc89-90602: His La tradición apostólica, 1986(hdg. on IObT rept.: Hippolytus, Antipope, ca. 170-235 or 6; usage: Hipólite de Roma)

found: Vagianos, G. S. To zētēma tou vaptismatos tōn pallakikōn ... 1990:title page (Hippolyto) page 518 (Hippolytos)

found: Visonà, G. Pseudo Ippolito, In sanctum Pascha, 1988:page 25, etc. (Pseudo-Hippolytus, name used for the author of the homily In sanctum Pascha discovered by Martin in 1926, thought by some to be a later text based on the lost homily of Hippolytus of Rome)