Sahih al-Bukhari 3764
Book 62: Companions of the Prophet · Narrated by Ibn Abu Mulaika
Arabic
حَدَّثَنَا الْحَسَنُ بْنُ بِشْرٍ، حَدَّثَنَا الْمُعَافَى، عَنْ عُثْمَانَ بْنِ الأَسْوَدِ، عَنِ ابْنِ أَبِي مُلَيْكَةَ، قَالَ أَوْتَرَ مُعَاوِيَةُ بَعْدَ الْعِشَاءِ بِرَكْعَةٍ وَعِنْدَهُ مَوْلًى لاِبْنِ عَبَّاسٍ، فَأَتَى ابْنَ عَبَّاسٍ فَقَالَ دَعْهُ، فَإِنَّهُ صَحِبَ رَسُولَ اللَّهِ صلى الله عليه وسلم.
English translation
Narrated Ibn Abu Mulaika:Muawiya offered one rak`a witr prayer after the `Isha prayer, and at that time a freed slave of Ibn `Abbas was present. He (i.e. the slave) went to Ibn `Abbas (and told him that Muawiya offered one rak`a witr prayer). Ibn `Abbas said, "Leave him, for he was in the company of Allah's Messenger (ﷺ)
Reference: Sahih al-Bukhari 3764, Book of Companions of the Prophet. English translation by Dr. Muhammad Muhsin Khan.