Sahih Muslim 748
صحيح مسلم#748SahihA'isha reported:A woman asked the Messenger of Allah (ﷺ) how to wash herself after menstruation. She mentioned that he taught her how to take bath and then told her to take a piece of cotton with musk and purify herself. She said: How should I purify myself with that? He (the Holy Prophet) said: Praise be to Allah, purify yourself with it, and covered his face, Sufyan b. 'Uyaina gave a demonstration by covering his face (as the Prophet had done). 'A'isha reported: I dragged her to my side for I had understood what the Messenger of Allah (ﷺ) intended and, therefore, said: Apply this cotton with musk to the trace of blood. Ibn 'Umar in his hadith (has mentioned the words of 'A'isha thus): Apply it to the marks of blood
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 3:70