Hadith 68:3
Narrated Ibn `Umar:
(Divorcing my wife during her menses) was counted as one legal divorce.
وَقَالَ أَبُو مَعْمَرٍ حَدَّثَنَا عَبْدُ الْوَارِثِ، حَدَّثَنَا أَيُّوبُ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عُمَرَ، قَالَ حُسِبَتْ عَلَىَّ بِتَطْلِيقَةٍ
Original Reference: Sahih al-Bukhari 5253