Sahih al-Bukhari 4489
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · The Statement of Allah "Verily! We have seen the turning of your (Muhammad's ) face towards the heaven..." (V.2:144)
Narrated Anas:
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ ، حَدَّثَنَا مُعْتَمِرٌ ، عَنْ أَبِيهِ ، عَنْ أَنَسٍ ـ رضى الله عنه ـ قَالَ لَمْ يَبْقَ مِمَّنْ صَلَّى الْقِبْلَتَيْنِ غَيْرِي.
None remains of those who prayed facing both Qiblas (that is, Jerusalem and Mecca) except myself.