Musnad Ahmad 1154:3

Ya'qub narrated to us, he said: My father narrated to me, from Muhammad ibn Ishaq, he said: Yazid ibn Abi Habib narrated to me, from Sulayman ibn Abi Sulayman, from his mother, Umm Sulayman—and both of them were trustworthy—she said: I entered upon Aisha, the wife of the Prophet, may Allah bless him and grant him peace, and I asked her about the meat of the sacrificial animals (al-adahi). She said: The Messenger of Allah, may Allah bless him and grant him peace, used to forbid it, then he granted a concession regarding it. Ali ibn Abi Talib arrived from a journey, and Fatima brought him meat from her sacrificial animals. He said: "Did the Messenger of Allah, may Allah bless him and grant him peace, not forbid it?" She said: "Indeed, he has granted a concession regarding it." She said: So Ali entered upon the Messenger of Allah, may Allah bless him and grant him peace, and asked him about that. He said to him: "Eat it from one Dhu al-Hijjah to the next Dhu al-Hijjah."