The Book of Games and the Animals which May be Slaughtered and the Aninals that Are to be Eaten (Kitab-us-Said wa'l-Dhaba'ih wa ma Yu'kalu min Al-Hayawan)
Muslim :: Book 21 : Hadith 4763
'Ali b. Abi Talib reported that Allah's Messenger (may peace be upon him) forbade on the Day of Khaibar temporary marriage (Muta') with women and the eating of the flesh of domestic asses.