´It was narrated that Anas bin Malik said:` "We were given a time limit with regard to trimming the mustache, shaving the pubic hairs, plucking the armpit hairs and clipping the nails. We were not to leave that for more than forty days."
Hadith ReferenceSunan Ibn Majah / The Book of Purification and its Sunnah / Hadith: 295
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم