Nathan P. Gibson, Vanessa Birkhahn and Hanna Friedel, (eds.), "Abū Zakkār — سعادة أبو زكار " in Communities of Knowledge: Interreligious Networks of Scholars in Ibn Abi Usaybiʿa’s History of the Physicians last modified June 23, 2021, https://usaybia.net/person/389 Abū Zakkār سعادة أبو زكار Abū Zakkār, singer under Hārūn al-Rashīd https://usaybia.net/person/389 singer A literary history of medicine: the 'Uyūn al-anbā' fī ṭabaqāt al-aṭibbā' of Ibn Abī Uṣaybi'ah 8.3.16