Sahih al-Bukhari, Book 9, Hadith 63 (In-Book) ⓘ
Narrated Muawiya: You offer a prayer which I did not see being offered by Allah's Messenger when we were in his company and he certainly had forbidden it (i.e. two rak`at after the `Asr prayer).
حَدَّثَنَا مُحَمَّدُ بْنُ أَبَانَ، قَالَ حَدَّثَنَا غُنْدَرٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي التَّيَّاحِ، قَالَ سَمِعْتُ حُمْرَانَ بْنَ أَبَانَ، يُحَدِّثُ عَنْ مُعَاوِيَةَ، قَالَ إِنَّكُمْ لَتُصَلُّونَ صَلاَةً، لَقَدْ صَحِبْنَا رَسُولَ اللَّهِ صلى الله عليه وسلم فَمَا رَأَيْنَاهُ يُصَلِّيهَا، وَلَقَدْ نَهَى عَنْهُمَا، يَعْنِي الرَّكْعَتَيْنِ بَعْدَ الْعَصْرِ.
also referenced under: Hadith 587 (DarusSalam) & Volume 1, Book 10, Hadith 561 (USC-MSA)