Sahih al-Bukhari 351
صحيح البخاري#351SahihNarrated Um `Atiya:We were ordered to bring out our menstruating women and veiled women in the religious gatherings and invocation of Muslims on the two `Id festivals. These menstruating women were to keep away from their Musalla. A woman asked, "O Allah's Messenger (ﷺ) ' What about one who does not have a veil?" He said, "Let her share the veil of her companion
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: 8:3