Sahih al-Bukhari 498

Arabic

حَدَّثَنَا مُسَدَّدٌ، قَالَ حَدَّثَنَا يَحْيَى، عَنْ عُبَيْدِ اللَّهِ، أَخْبَرَنِي نَافِعٌ، عَنْ عَبْدِ اللَّهِ، أَنَّ النَّبِيَّ صلى الله عليه وسلم كَانَ يُرْكَزُ لَهُ الْحَرْبَةُ فَيُصَلِّي إِلَيْهَا‏.‏

English translation

Narrated `Abdullah:The Prophet (ﷺ) used to get a Harba planted in front of him (as a Sutra) and pray behind it

Reference: Sahih al-Bukhari 498, Book of Prayers (Salat). English translation by Dr. Muhammad Muhsin Khan.