大越史記全書
Although being the Emperor of Đại Việt, Phế Đế was only a "de jure" ruler because it was Nghệ Tông who still held the real power. According to "Đại Việt sử ký toàn thư", Phế Đế was actually worse than his father, he had a weak and ignorant character which was profited by Hồ Quý Ly in his gradual control of royal court.