حَدَّثَنَا أَحْمَدُ بْنُ عَبْدِ اللَّهِ بْنِ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا أَبُو إِسْحَاقَ، حَدَّثَنِي حَارِثَةُ بْنُ وَهْبٍ الْخُزَاعِيُّ، قَالَ صَلَّيْتُ خَلْفَ رَسُولِ اللَّهِ صلى الله عليه وسلم بِمِنًى وَالنَّاسُ أَكْثَرُ مَا كَانُوا فَصَلَّى رَكْعَتَيْنِ فِي حَجَّةِ الْوَدَاعِ ‏.‏ قَالَ مُسْلِمٌ حَارِثَةُ بْنُ وَهْبٍ الْخُزَاعِيُّ هُوَ أَخُو عُبَيْدِ اللَّهِ بْنِ عُمَرَ بْنِ الْخَطَّابِ لأُمِّهِ ‏.‏

Wahb al-Khuza'i reported: I prayed behind the Messenger of Allah (way peace be upon him) at Mina, and there was the greatest number of people, and they prayed two rak'ahs on the occasion of the Farwell Pilgrmage. (Muslim said: Haritha b. Wahb al-Khuza'i is the brother of 'Ubaidullah b. 'Umar son of Khattab from the side of mother.) Translation Not Available

Book Ref: Sahih Muslim Book 6 Hadith 1486
Web Ref:  Sahih Muslim Book 4 Hadith 696 b