Sahih Muslim 601
صحيح مسلم#601SahihIbn Umar said:The Apostle of Allah (ﷺ) ordered us to trim the moustache closely and spare the beard
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: 2:68