(1) باب الْفِطْرَةِ
It was narrated that Abu Hurairah said:
"The Messenger of Allah [SAW] said: 'Five things are of the Fitrah: Circumcision, shaving the pubes, plucking the armpit hair, clipping the nails and trimming the mustache.'" (FR)
Reference (FR): Sunan an-Nasa'i 5043 (FR)
In-book reference (FR): Book 48, Hadith 4 (FR)
English translation (FR): Vol. 6, Book 48, Hadith 5046 (FR)