Sahih al-Bukhari 3764
Sahih al-Bukhari · Book 62: Companions of the Prophet · Narration about Mu'awiya رضي الله عنه
Narrated Ibn Abu Mulaika:
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.
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)."