In the poem he is called Eutropis (genitive: Eutropitis), not Eutropius. Venantius Fortunatus (1881). Leo, Friedrich (ed.). Venanti Honori Clementiani Fortunati presbyteri Italici opera poetica. Monumenta Germaniae Historica. Vol. Tomus IV, pars prior. Berlin: Weidmann. pp. I. 13, p. 15.
"The Glory of the Martyrs", Gregorius (Turonensis) (1583). De gloria martyrum (in Latin). Cologne: Cholinus. p. 75.
The mention of the martyrdom, found in Gregory of Tours, does not feature in Venantius. Eustella is introduced by the fourteenth century bishop of Equilio, Petrus de Natalibus: G. Henschenius, in: Acta sanctorum: Acta sanctorum Aprilis (in Latin). Vol. Tomus III. Antwerp: Michael Cholinus. 1675. p. 735. See in general: Michael John Roberts (2009). The Humblest Sparrow: The Poetry of Venantius Fortunatus. Ann Arbor: University of Michigan Press. pp. 169, note 15. ISBN978-0-472-11683-6.
Georges Musset, "Les insinuations ecclésiastiques dans le diocèse de Saintes au cours de l'année 1565," Archives historiques de la Saintonge et de l'Aunis. Vol. 35. Paris: Mme. Z. Mortreuil. 1905. pp. 260–261.
Louis Audiat (1897). Deux victimes des septembriseurs (in French). Lille-Paris: Societé de Saint-Augustin, Descleé, de Brouwer et cie.
Georges Musset, "Les insinuations ecclésiastiques dans le diocèse de Saintes au cours de l'année 1565," Archives historiques de la Saintonge et de l'Aunis. Vol. 35. Paris: Mme. Z. Mortreuil. 1905. pp. 260–261. Grasilier, pp. 52–53.
Salvador Miranda, Librarian Emeritus, Florida International University, The Cardinals of the Holy Roman Church"Soderini, Francesco", retrieved: 2016-08-11.