Sahih Bukhari Volume 7, Book 63, Hadith Number 186.

Narrated By ‘Aisha : The wife of Rifa’a Al-Qurazi came to Allah’s Apostle and said, “O Allah’s Apostle! Rifa’a divorced me irrevocably. After him I married ‘Abdur-Rahman bin Az-Zubair Al-Qurazi who proved to be impotent.” Allah’s Apostle said to her, “Perhaps you want to return to Rifa’a? Nay (you cannot return to Rifa’a) until you and ‘Abdur-Rahman consummate your marriage.”