Musannaf Ibn Abi Shayba 3:3283

Ibn Mahdi narrated to us, from Za'idah, from Simak, who said: I saw al-Mughirah ibn Shu'bah, al-Dahhak, and Ziyad praying on the day of al-Fitr and al-Adha without an Adhan and without an Iqamah.