↑ 1,01,1(en) Davis, R (2001). Book of the Pontiffs (English Translation of the Liber Pontificalis). Liverpool University Press. ISBN0-85323-545-7.
↑(en) Weber, Nicholas (1912). "Pope St. Sixtus III". The Catholic Encyclopedia. Vol 14. New York: Robert Appleton Company. Besoek op 15 September 2017.
Eksterne skakels
Wikimedia Commons bevat media in verband met Sixtus III.
BBKL Inskrywing (met Literatuurverwysings) in die Biographisch-Bibliographisches Kirchenlexikon (Duits)