The Book of Menstruation (Kitab Al-Haid)
Muslim :: Book 3 : Hadith 733
Qatida reported: I heard Anas as saying that the Companion of the Messenger of Allah (may peace be upon him) dozed off and then offered prayer and did not perform ablution. He (the narrator) said: I asked him if he had actually heard it from Anas. He said: By Allah. yes.