Hadith 1667
Chapter 26: How to pray at night - كتاب قيام الليل وتطوع النهار
أَخْبَرَنَا مُحَمَّدُ بْنُ قُدَامَةَ، قَالَ حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ حَبِيبٍ، عَنْ طَاوُسٍ، قَالَ قَالَ ابْنُ عُمَرَ سَأَلَ رَجُلٌ رَسُولَ اللَّهِ صلى الله عليه وسلم عَنْ صَلاَةِ اللَّيْلِ فَقَالَ " مَثْنَى مَثْنَى فَإِذَا خَشِيتَ الصُّبْحَ فَوَاحِدَةٌ " .
It was narrated that Tawus said:
"Ibn Umar said: "A man asked the Messenger of Allah (ﷺ) about prayer at night. He said: "Two by two, and if you fear that dawn will come, then one.'"
Reference : Sunan an-Nasa'i 1667
In-book reference : Book 20, Hadith 70