Sahih Bukhari
Sales and Trade
Volume: 003 / Book Number: 034 / Hadith Number: 273
Narrated 'Aisha:
Some people said, "O Allah's Apostle! Meat is brought to us by some people and we are not sure whether the name of Allah has been mentioned on it or not (at the time of slaughtering the animals)." Allah's Apostle said (to them), "Mention the name of Allah and eat it."