Hadithcore
Sahih al-Bukhari, 353
sahih

Narrated Muhammad bin Al Munkadir:

I saw Jabir bin `Abdullah praying in a single garment and he said that he had seen the Prophet (ﷺ) praying in a single garment.

حَدَّثَنَا مُطَرِّفٌ أَبُو مُصْعَبٍ، قَالَ حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ أَبِي الْمَوَالِي، عَنْ مُحَمَّدِ بْنِ الْمُنْكَدِرِ، قَالَ رَأَيْتُ جَابِرَ بْنَ عَبْدِ اللَّهِ يُصَلِّي فِي ثَوْبٍ وَاحِدٍ وَقَالَ رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يُصَلِّي فِي ثَوْبٍ‏.‏

References2 variants
In-Book Reference
Book 8, Hadith 5
USC-MSA web (English) reference
Vol. 1, Book 8, Hadith 349 (deprecated numbering scheme)