Musannaf Ibn Abi Shayba 3:3469

Abdullah ibn Numayr narrated to us, from Isra'il, from Uthman al-Thaqafi, from Abu Ramla al-Shami, who said: I witnessed Mu'awiya asking Zayd ibn Arqam, "Did you witness with the Messenger of Allah, may Allah bless him and grant him peace, two Eids that occurred together?" He said, "Yes." He asked, "So how did he act?" He said, "He prayed the Eid, then he granted a concession regarding the Jumu'ah, saying, 'Whoever wishes to pray, let him pray.'"