Abu Dawud
Divorce
Book Number: 006 / Hadith Number: 2194
Narated By Abdullah ibn Abbas : Tawus said: AbusSahba' said to Ibn Abbas: Do you know that a divorce by three pronouncements was made a single one during the time of the Prophet (pbuh), and of AbuBakr and in the early days of the caliphate of Umar? He replied: Yes.