Thurston 1909, pp. 453–455. Thurston, Herbert (1909), "St. George", The Catholic Encyclopedia, vol. 6, New York City, New York: Robert Appleton Company, pp. 453–455, retrieved 25 March 2018
Düwel 2005, p. 114-115. Düwel, Klaus (2005). "Sigurddarstellung". In Beck, Heinrich; Geuenich, Dieter; Steuer, Heiko (eds.). Reallexikon der Germanischen Altertumskunde. Vol. 28. New York/Berlin: de Gruyter. pp. 412–422.
Kiessling, Nicolas K. (1970). "Antecedents of the Medieval Dragon in Sacred History". Journal of Biblical Literature. 89 (2): 167–177. doi:10.2307/3263046. JSTOR3263046.
Nickel, Helmut (1989). "Of Dragons, Basilisks, and the Arms of the Seven Kings of Rome". Metropolitan Museum Journal. 24: 25–34. doi:10.2307/1512864. JSTOR1512864. S2CID191378315.
Scobie, Alex (July 1977). "An Ancient Greek Drakos-Tale in Apuleius' Metamorphoses VIII, 19-21". The Journal of American Folklore. 90 (357): 339–343. doi:10.2307/539524. JSTOR539524.
Fatás, Guillermo (19 May 2019). "Dragones buenos, dragones malos". Heraldo de Aragón (in Spanish). decir dragón era casi decir ‘de Aragón’. Retrieved 2020-01-25.
Kiessling, Nicolas K. (1970). "Antecedents of the Medieval Dragon in Sacred History". Journal of Biblical Literature. 89 (2): 167–177. doi:10.2307/3263046. JSTOR3263046.
Nickel, Helmut (1989). "Of Dragons, Basilisks, and the Arms of the Seven Kings of Rome". Metropolitan Museum Journal. 24: 25–34. doi:10.2307/1512864. JSTOR1512864. S2CID191378315.
Scobie, Alex (July 1977). "An Ancient Greek Drakos-Tale in Apuleius' Metamorphoses VIII, 19-21". The Journal of American Folklore. 90 (357): 339–343. doi:10.2307/539524. JSTOR539524.
Nickel, Helmut (1989). "Of Dragons, Basilisks, and the Arms of the Seven Kings of Rome". Metropolitan Museum Journal. 24: 25–34. doi:10.2307/1512864. JSTOR1512864. S2CID191378315.