Musnad Ahmad 160:1

'Abd al-Rahman narrated to us, from Sufyan, from 'Abdullah—meaning Ibn Abi Bakr—and Salim Abu al-Nadr, from Sulayman ibn Yasar, from 'Abdullah ibn Hudhafah: "That the Prophet, peace and blessings of Allah be upon him, commanded him to announce during the Days of Tashriq: 'They are days of eating and drinking.'"