The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fada'il)
Muslim :: Book 30 : Hadith 5659
Anas reported Allah's Apostle (may peace be upon him) was at az-Zaura' and a vessel containing water was brought to him in which his finger could not be completely dipped or completely covered; the rest of the hadith is the same.