أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا الْمُعْتَمِرُ، قَالَ سَمِعْتُ عُبَيْدَ اللَّهِ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ إِذَا لَمْ يُجْمِعِ الرَّجُلُ الصَّوْمَ مِنَ اللَّيْلِ فَلاَ يَصُمْ ‏.‏

It was narrated that Ibn 'Umar said: "If a man does not intend to fast from the night before, he should not fast." Translation Not Available

Book Ref: Sunan An Nisai Book 22 Hadith 2342
Web Ref:  Sunan An Nisai Vol 3 Book 22 Hadith 2344