Sunan an-Nasa'i 579
سنن النسائي#579Sahihأَخْبَرَنِي مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا الْمُعْتَمِرُ، قَالَ سَمِعْتُ مَعْمَرًا، عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ أُمِّ سَلَمَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم صَلَّى فِي بَيْتِهَا بَعْدَ الْعَصْرِ رَكْعَتَيْنِ مَرَّةً وَاحِدَةً وَأَنَّهَا ذَكَرَتْ ذَلِكَ لَهُ فَقَالَ " هُمَا رَكْعَتَانِ كُنْتُ أُصَلِّيهِمَا بَعْدَ الظُّهْرِ فَشُغِلْتُ عَنْهُمَا حَتَّى صَلَّيْتُ الْعَصْرَ " .
It was narrated from Umm Salamah that the Prophet (ﷺ) once prayed two Rak'ahs after 'Asr in her house. She asked him about that and he said:"They are two Rak'ahs that I used to pray after Zuhr, but I got distracted and forgot them until I prayed 'Asr
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 6:86