´It was narrated that Abu Hurairah said:` "The Messenger of Allah mentioned the crescent and said: 'When you see it, fast and when you see it, stop fasting, and if it is obscured from you (too cloudy), then count thirty days."'
Hadith ReferenceSunan an-Nasa'i / The Book of Fasting / Hadith: 2125
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم