Sunan an-Nasa'i, Hadith 2209 ⓘ
A similar report was narrated from Abu Salamah and he said: "Whoever fasts it and spends its nights in prayer out of faith and in the hope of reward." (Daif)
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا النَّضْرُ بْنُ شُمَيْلٍ، قَالَ أَنْبَأَنَا الْقَاسِمُ بْنُ الْفَضْلِ، قَالَ حَدَّثَنَا النَّضْرُ بْنُ شَيْبَانَ، عَنْ أَبِي سَلَمَةَ، فَذَكَرَ مِثْلَهُ وَقَالَ " مَنْ صَامَهُ وَقَامَهُ إِيمَانًا وَاحْتِسَابًا " .
also referenced under: Book 22, Hadith 120 (In-Book) & Volume 3, Book 22, Hadith 2211 (DarusSalam)