(55) باب تَفْضِيلِ الْحَلْقِ عَلَى التَّقْصِيرِ وَجَوَازِ التَّقْصِيرِ
Ubaidullah reported this hadith with the same chain of transmitters and (it is said) that it was on the fourth turn that he (the Holy Prophet) said:
(May Allah have mercy upon) those who got their hair clipped."
Reference: Sahih Muslim 1301 d
In-book reference: Book 15, Hadith 351
USC-MSA web (English) reference(deprecated numbering scheme): Book 7, Hadith 2986