http://www.christiananswers.net/q-aig/aig-c034.html contains information about the correlation between Flat Earth and the Church; though it is written from a Christian Apologetics point of view, the information is factual.
dmgh.de
MGH, Epistolae Selectae 1, 80, pp. 178-9.[2]; translation in M. L. W. Laistner, Thought and Letters in Western Europe: A.D. 500 to 900, 2nd. ed., (Ithaca: Cornell Univ. Pr., 1955), pp. 184-5.
gwdg.de
webdoc.sub.gwdg.de
Klaus Anselm Vogel, "Sphaera terrae - das mittelalterliche Bild der Erde und die kosmographische Revolution," PhD dissertation Georg-August-Universität Göttingen, 1995, p. 19.[3]
human-nature.com
A. D. White, A History of the Warfare of Science with Theology in Christendom, (New York: D. Appleton & Co., 1896)[5].
Isidoro de Sevilo, Etymologiae, XIV.ii.1 (el The Latin Library); Wesley M. Stevens, "The Figure of the Earth in Isidore's De natura rerum", Isis, 71(1980): 268-277.
