Sahih Muslim
The Book of Marriage (Kitab Al-Nikah)
Book Number: 008 / Hadith Number: 3379
Ma'bad b. Sirin said to Abu Sa'id (Allah be pleased with him): Did you hear Allah's Messenger (may peace be upon him) making a mention of something in regard to al-'azl? Thereupon he said: Yes. The rest (of the hadith is the same)