Sunan an-Nasa'i, Hadith 469 ⓘ
It was narrated from Ibn Al-Munkadir and Ibrahim bin Maisarah, that they heard Anas say: "I prayed Zuhr with the Prophet in Al-Madinah, four Rak'ahs and 'Asr in Dhul-Hulaifah, two Rak'ahs."
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنِ ابْنِ الْمُنْكَدِرِ، وَإِبْرَاهِيمَ بْنِ مَيْسَرَةَ، سَمِعَا أَنَسًا، قَالَ صَلَّيْتُ مَعَ النَّبِيِّ صلى الله عليه وسلم الظُّهْرَ بِالْمَدِينَةِ أَرْبَعًا وَبِذِي الْحُلَيْفَةِ الْعَصْرَ رَكْعَتَيْنِ .
also referenced under: Book 5, Hadith 22 (In-Book) & Volume 1, Book 5, Hadith 470 (DarusSalam)