Sahih Bukhari | Volume 3 | Hadith Number 273

Narrated by '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."