Essay Review: Early Medieval Planetary Astronomy: The Revival of Planetary Astronomy in Carolingian and Post-Carolingian Europe

Abbo Flury , De ratione spere , 170–185. Ed. by Thomson Ron B. , “Two astronomical tractates of Abbo of Fleury”, pp. 113–33 in North J. D. Roche J. J. (eds), The light of nature (Dordrecht, 1985). It may be significant that Abbo's calculated position places Mars in the same constellation as do modern calculations.