Sahih al-Bukhari 333
صحيح البخاري#333SahihNarrated Maimuna:(the wife of the Prophet) During my menses, I never prayed, but used to sit on the mat beside the mosque of Allah's Messenger (ﷺ). He used to offer the prayer on his sheet and in prostration some of his clothes used to touch me
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 6:37