Hadith 686
Chapter 253: What May Be Used As A Sutrah By The Praying Person - كتاب الصلاة
حَدَّثَنَا الْحَسَنُ بْنُ عَلِيٍّ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، عَنِ ابْنِ جُرَيْجٍ، عَنْ عَطَاءٍ، قَالَ آخِرَةُ الرَّحْلِ ذِرَاعٌ فَمَا فَوْقَهُ .
'Ata said:
The back of the saddle is (about) one cubit (in height) or more than that.
Reference : Sunan Abi Dawud 686
In-book reference : Book 2, Hadith 296