Sahih al-Bukhari 230
صحيح البخاري#230SahihNarrated Sulaiman bin Yasar:I asked `Aisha about the clothes soiled with semen. She replied, "I used to wash it off the clothes of Allah's Messenger (ﷺ) and he would go for the prayer while water spots were still visible
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: 4:96