Sahih Muslim Book 2, Hadith Number 539.
Chapter : Time limit for wiping over the shoes.
Shuraib b. Hani reported: I asked ‘Aisha about wiping over the shoes. She said: You better go to ‘Ali, for he knows more about this than I. I, therefore, came to ‘Ali and he narrated from the Apostle (may peace be upon him) like this.