The Book of Purification
1/2. Chapter:
(Using) Siwak When Arising During The Night
Sunan an-Nasai
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، وَقُتَيْبَةُ بْنُ سَعِيدٍ، عَنْ جَرِيرٍ، عَنْ مَنْصُورٍ، عَنْ أَبِي وَائِلٍ، عَنْ حُذَيْفَةَ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا قَامَ مِنَ اللَّيْلِ يَشُوصُ فَاهُ بِالسِّوَاكِ .
It was narrated that Huthaifah said: "When the Messenger of Allah (ﷺ) got up at night, he would brush his mouth with the Siwak."
Reference : Sunan an-Nasa'i 2In-book reference : Book 1, Hadith 2English translation : Vol. 1, Book 1, Hadith 2