ENOfficial
Narrated Nafi`: "I saw Ibn `Umar praying while taking his camel as a Sutra in front of him and he said, "I saw the Prophet doing the same."
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا صَدَقَةُ بْنُ الْفَضْلِ، قَالَ أَخْبَرَنَا سُلَيْمَانُ بْنُ حَيَّانَ، قَالَ حَدَّثَنَا عُبَيْدُ اللَّهِ، عَنْ نَافِعٍ، قَالَ رَأَيْتُ ابْنَ عُمَرَ يُصَلِّي إِلَى بَعِيرِهِ وَقَالَ رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يَفْعَلُهُ.
sunnah.com