The Book of Purification (Kitab Al-Taharah) 
Muslim :: Book 2 : Hadith 548
Abu Huraira reported: The Messenger of Allah (may peace be upon him) said: When a dog drinks out of a vessel belonging to any one of you, he must wash it seven times.
The Book of Purification (Kitab Al-Taharah)
Muslim :: Book 2 : Hadith 548
Abu Huraira reported: The Messenger of Allah (may peace be upon him) said: When a dog drinks out of a vessel belonging to any one of you, he must wash it seven times.