سُنَنُ النَّسَائِيِّ
Sunan an-Nasa’i 1671
The Book of Qiyam Al-Lail (The Night Prayer) and Voluntary Prayers During the Day
How to pray at night
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ صَلاَةُ اللَّيْلِ مَثْنَى مَثْنَى فَإِذَا خِفْتَ الصُّبْحَ فَأَوْتِرْ بِوَاحِدَةٍ .
It was narrated from Ibn Umar that: The Prophet (ﷺ) said: "prayers at night are (offered) two by two, then if you fear that dawn will come, pray witr with one."
Sunan an-Nasa'i, 1671Sahih (Darussalam)