The Book of Divorce (Kitab Al-Talaq)
Muslim :: Book 9 : Hadith 3492
Abu Sahba' said toIbn 'Abbas (Allah be pleased with them): Do you know that three (divorces) were treated as one during the lifetime of Allah's Apostle (may peace be upon him), and that of Abu Bakr, and during three (years) of the caliphate of Umar (Allah be pleased with him)? Ibn Abbas (Allah be pleased with them) said: Yes.