Muwatta Malik 324
موطأ مالك#324SahihYahya related to me from Malik from a reliable source from Bukayr ibn Abdullah ibn al-Ashajj from Busr ibn Said that when Ubaydullah ibn al-Aswad al-Khawlani was in the room of Maimuna, the wife of the Prophet, may Allah bless him and grant him peace, she used to pray in a shift and head-covering, without a waist-wrapper
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Salim al-HilaliMauquf Sahih
In-book reference: 8:38