Sunan Ibn Majah, Volume 2, Book 5, Hadith 1365 (DarusSalam) ⓘ
It was narrated that ‘Aishah said: “The Messenger of Allah used to sleep during the first part of the night and stay awake during the latter part.”
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عُبَيْدُ اللَّهِ، عَنْ إِسْرَائِيلَ، عَنْ أَبِي إِسْحَاقَ، عَنِ الأَسْوَدِ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ يَنَامُ أَوَّلَ اللَّيْلِ وَيُحْيِي آخِرَهُ .
also referenced under: Hadith 1365 (Reference) & Book 5, Hadith 1427 (In-Book)