(10) باب ذِكْرِ الاِخْتِلاَفِ عَلَى الزُّهْرِيِّ فِي هَذَا الْحَدِيثِ
It was narrated from Ibn 'Umar that the Messenger of Allah mentioned Ramadan and said:
"Do not fast until you see the crescent, and do not stop fasting until you see it, and if it is obscured from you (too cloudy), then work it out."
Reference: Sunan an-Nasa'i 2121
In-book reference: Book 22, Hadith 32
English translation: Vol. 3, Book 22, Hadith 2123