حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنْ أَبِي الزُّبَيْرِ، عَنْ جَابِرٍ، - قَالَ - بَعَثَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم فِي حَاجَةٍ قَالَ فَجِئْتُ وَهُوَ يُصَلِّي عَلَى رَاحِلَتِهِ نَحْوَ الْمَشْرِقِ وَالسُّجُودُ أَخْفَضُ مِنَ الرُّكُوعِ ‏.‏

Narrated Jabir ibn Abdullah: The Messenger of Allah (PBUH) sent me on some business, and when I came to him he was praying on (the back of) his riding beast (moving) towards the east and making the prostration lower than the bowing. Translation Not Available

Book Ref: Sunan Abi Dawud Book 4 Hadith 1227
Web Ref:  Sunan Abi Dawud Book 4 Hadith 1223