Complex sentence: The stated reason was the degree of consanguinity between the two by Pope Gregory V. Eleanor Shipley Duckett, "Death and Life in the Tenth Century", (University of Michigan Press, 1988), 130.
Split into simpler sentences: The stated reason was the degree of consanguinity between the two. By Pope Gregory V. Eleanor Shipley Duckett, "Death and Life in the Tenth Century", (University of Michigan Press, 1988), 130.