The Book of Sacrifices (Kitab Al-Adahi)
Muslim :: Book 22 : Hadith 4855
Ibn 'Umar reported that Allah's Messenger (may peace be upon him) forbade that the flesh of sacrificial animals be eaten beyond three (days) Salim (son of Ibn Umar) said: Ibn 'Umar did not eat the flesh of the sacrificial animals beyond three (days). Ibn Abu 'Umar said:" Beyond three days."