Sunan Abi Dawud 4194
سنن أبي داود#4194SahihNarrated Abdullah ibn Umar: the Prophet (ﷺ) forbade qaza' which means that the head of a boy is shaved and a lock is left
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 35:36