It is narrated from Tawus that Abu As-Sahba asked Ibn Abbas (may Allah be pleased with them), "Were three divorces counted as only one during the time of the Messenger of Allah (ﷺ), the caliphate of Abu Bakr (may Allah be pleased with him), and the first three years of the caliphate of Umar (may Allah be pleased with him)?" Ibn Abbas (may Allah be pleased with them) replied, "Yes."
Hadith Referenceمسند الإمام الشافعي / كتاب الطلاق / 1246
Hadith Takhrijاخرجه مسلم ، الطلاق باب طلاق الثلاث (1472)۔