سُنَنُ النَّسَائِيِّ
Sunan an-Nasa’i 1762
The Book of Qiyam Al-Lail (The Night Prayer) and Voluntary Prayers During the Day
Lying down on one's right side after the two rak'ahs of Fajr
أَخْبَرَنَا عَمْرُو بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا عَلِيُّ بْنُ عَيَّاشٍ، قَالَ حَدَّثَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي عُرْوَةُ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا سَكَتَ الْمُؤَذِّنُ بِالأُولَى مِنْ صَلاَةِ الْفَجْرِ قَامَ فَرَكَعَ رَكْعَتَيْنِ خَفِيفَتَيْنِ قَبْلَ صَلاَةِ الْفَجْرِ بَعْدَ أَنْ يَتَبَيَّنَ الْفَجْرُ ثُمَّ يَضْطَجِعُ عَلَى شِقِّهِ الأَيْمَنِ .
It was narrated that Aishah said: "When the Muaddhin fell silent after the Adhan for the beginning of Fajr, he would pray two brief rak'ahs, then he would lie down on his right side."
Sunan an-Nasa'i, 1762Sahih (Darussalam)