Sahih Muslim Book 4, Hadith Number 743.
Chapter : How Adhan is to be pronounced.
‘Aisha reported: Ibn Umm Maktum used to pronounce Adhan at the behest of the Messenger of Allah (may peace be upon him) (despite the fact) that he was blind.
‘Aisha reported: Ibn Umm Maktum used to pronounce Adhan at the behest of the Messenger of Allah (may peace be upon him) (despite the fact) that he was blind.