(en) Sint Johannes Chrysostomus: Homilies Concerning the Statutes, Homily IX [4], paras. 7-8, in A SELECT LIBRARY OF THE NICENE AND POST-NICENE FATHERS OF THE CHRISTIAN CHURCH, Series I, Vol IX, ed. Philip Schaff, D.D.,LL.D., Amerikaanse herdruk van de Edinburgh edition (1978), W.B.Eerdmans Publishing Co., Grand Rapids, MI, pp. 403-404
Monumenta Germaniae Historica, Epistolae Selectae 1, 80, pp. 178-9.[10]; Engelse vertaling in: Laistner, M.L.W.: Thought and Letters in Western Europe: A.D. 500 to 900, 2e druk, Cornell Universoty Press, Ithaca, pp. 184-5
(en) Anaximandros, Fragments and Commentary; Engelse bewerking en vertaling: Fairbanks, A. (Plut., Strom. 2 ; Dox. 579); geciteerd uit het Hanover Historical Texts Project. [1]
(en) Livingston, M., 2002: strangehorizons.com; Modern Medieval Map Myths: The Flat World, Ancient Sea-Kings, and Dragons