Nashaʾt al-Qāhirah wa-imtidāduhu fī ayyām al-Ayyūbīyīn - Zakī, ʿAbd al-Raḥmān (al-Majallah al-Tārīkhīyah al-Miṣrīyah [= Ägyptische historische Zeitschrift], 18.1971, 1971)