(33) باب مَا جَاءَ لاَ صِيَامَ لِمَنْ لَمْ يَعْزِمْ مِنَ اللَّيْلِ
Hafsah narrated that:
the Prophet said: "Whoever did not decide to fast before Fajr then there is no fast for him." (FR)
Reference (FR): Jami` at-Tirmidhi 730 (FR)
In-book reference (FR): Book 8, Hadith 49 (FR)
English translation (FR): Vol. 2, Book 3, Hadith 730 (FR)