The Book of Marriage (Kitab Al-Nikah)
Muslim :: Book 8 : Hadith 3320
Anas b. Malik (Allah be pleasedwith him) reported that 'Abd al-Rahman b. 'Auf (Allah be pleased with him) married during the lifetime of Allah's Messenger (may peace be upon him) for a nawat weight of gold and the messenger of Allah (may peace be upon him) said to him: Give a feast even with a sheep.