Cristea, O. The Quest for Maritime Supremacy in the Black Sea during the later Middle Ages: Ovidiu Cristea. The Balkans and Caucasus : parallel processes on the opposite sides of the Black Sea.(2012).

Cristea, Ovidiu. "The Quest for Maritime Supremacy in the Black Sea During the Later Middle Ages: Ovidiu Cristea." The Balkans and Caucasus : Parallel Processes on the Opposite Sides of the Black Sea.(2012) .

Cristea, Ovidiu. "The Quest for Maritime Supremacy in the Black Sea During the Later Middle Ages: Ovidiu Cristea." The Balkans and Caucasus : Parallel Processes on the Opposite Sides of the Black Sea.(2012), .