Sunan an-Nasa'i, Volume 3, Book 24, Hadith 2919 (DarusSalam) ⓘ
It was narrated that Usmah said: "The Messenger of Allah came out of the House and prayed two Rakahs in front of the Kabah, then he said: 'This is the Qiblah.'"
أَخْبَرَنَا إِسْمَاعِيلُ بْنُ مَسْعُودٍ، قَالَ حَدَّثَنَا خَالِدٌ، عَنْ عَبْدِ الْمَلِكِ، عَنْ عَطَاءٍ، عَنْ أُسَامَةَ، قَالَ خَرَجَ رَسُولُ اللَّهِ صلى الله عليه وسلم مِنَ الْبَيْتِ صَلَّى رَكْعَتَيْنِ فِي قُبُلِ الْكَعْبَةِ ثُمَّ قَالَ " هَذِهِ الْقِبْلَةُ " .
also referenced under: Hadith 2916 (Reference) & Book 24, Hadith 0 (In-Book)