Sunan an-Nasa'i 5
سنن النسائي#5SahihAbdur-Rahman bin Abu 'Atiq said:"My father told me: 'I heard 'Aishah say, (narrating) from the Prophet (ﷺ): "Siwak is a means of purification for the mouth and is pleasing to the Lord
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih
In-book reference: 1:5