Sahih al-Bukhari 312
صحيح البخاري#312SahihNarrated `Aisha:None of us had more than a single garment and we used to have our menses while wearing it. Whenever it got soiled with blood of menses we used to apply saliva to the blood spot and rub off the blood with our nails
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: 6:17