Sahih al-Bukhari 996
Book 14: Witr Prayer · Narrated by `Aisha
Arabic
حَدَّثَنَا عُمَرُ بْنُ حَفْصٍ، قَالَ حَدَّثَنَا أَبِي قَالَ، حَدَّثَنَا الأَعْمَشُ، قَالَ حَدَّثَنِي مُسْلِمٌ، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ، قَالَتْ كُلَّ اللَّيْلِ أَوْتَرَ رَسُولُ اللَّهِ صلى الله عليه وسلم وَانْتَهَى وِتْرُهُ إِلَى السَّحَرِ.
English translation
Narrated `Aisha:Allah's Messenger (ﷺ) offered witr prayer at different nights at various hours extending (from the `Isha' prayer) up to the last hour of the night
Reference: Sahih al-Bukhari 996, Book of Witr Prayer. English translation by Dr. Muhammad Muhsin Khan.