Hadith 5507
Narrated `Aisha: A group of people said to the Prophet, "Some people bring us meat and we do not know whether they have mentioned Allah's Name or not on slaughtering the animal." He said, "Mention Allah's Name on it and eat." Those people had embraced Islam recently.
Hadith 7398
Narrated `Aisha: The people said to the Prophet , "O Allah's Apostle! Here are people who have recently embraced Islam and they bring meat, and we do not know whether they had mentioned Allah's Name while slaughtering the animals or not." The Prophet said, "You should mention Allah's Name and eat."