Agapio, Kitab al-'Unvan [Universala Historio], p. 653
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Maududi, Syed Abul Ala. Tafhim al-Qur'an. “The identification ... has been a controversial matter from the earliest times. In general the commentators have been of the opinion that he was Alexander the Great but the characteristics of Zul-Qarnain described in the Qur'an are not applicable to him. However, now the commentators are inclined to believe that Zul-Qarnain was Cyrus ... We are also of the opinion that probably Zul-Qarnain was Cyrus...”.