Hadith 10:738
Abu Bakr narrated to us, he said: Yahya ibn Sa’id narrated to us, from ‘Ubayd Allah ibn ‘Umar, from Nafi’, from Ibn ‘Umar, that al-Rubayyi’ obtained khul’ (divorce initiated by the wife) from her husband. So her paternal uncle came to ‘Uthman, and he said: "She shall observe an ‘iddah (waiting period) of one menstrual cycle." Ibn ‘Umar used to say: "She shall observe an ‘iddah of three menstrual cycles," until ‘Uthman said this. Then he (Ibn ‘Umar) began to issue fatwas according to it, and he would say: "He is the best of us and the most knowledgeable of us."
حدثنا أبو بكر قال نا يحيى بن سعيد عن عبيد الله بن عمر عن نافع عن بن عمر أن الربيع اختلعت من زوجها فأتى عمها عثمان فقال تعتد بحيضة وكان بن عمر يقول تعتد ثلاث حيض حتى قال هذا عثمان فكان يفتي به ويقول خيرنا وأعلمنا