Sunan an-Nasa'i 5048
سنن النسائي#5048SahihIt was narrated from Ibn 'Umar that :The Prophet [SAW] saw a boy, part of whose head had been shaven and part had been left. He forbade that and said: "Shave all of it, or leave all of it
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 48:9