Analysis of information sources in references of the Wikipedia article "Al-Muzaffar Ahmad" in English language version.
...(January 13th, 1421), and another infant son, Aḥmad, was proclaimed with the title Malik al-Moẓaffar, the proclamation being followed by the usual dissensions between the amirs, ending with the assumption of supreme power by the amir Tatar, who, after defeating his rivals, on the 29th of August 1421 had himself proclaimed sultan with the title Malik al-Ẓāhir