Sahih al-Bukhari 1225
Sahih al-Bukhari · Book 22: Forgetfulness in Prayer · What is said regarding the Sahw: If someone gets up (for the third rak'a without sitting) after the second rak'a of a compulsory salat (prayer)
Narrated `Abdullah bin Buhaina:
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ ، أَخْبَرَنَا مَالِكٌ ، عَنْ يَحْيَى بْنِ سَعِيدٍ ، عَنْ عَبْدِ الرَّحْمَنِ الأَعْرَجِ ، عَنْ عَبْدِ اللَّهِ ابْنِ بُحَيْنَةَ ـ رضى الله عنه ـ أَنَّهُ قَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَامَ مِنِ اثْنَتَيْنِ مِنَ الظُّهْرِ لَمْ يَجْلِسْ بَيْنَهُمَا، فَلَمَّا قَضَى صَلاَتَهُ سَجَدَ سَجْدَتَيْنِ ثُمَّ سَلَّمَ بَعْدَ ذَلِكَ.
Allah's Messenger (ﷺ) got up after the second rak`a of the Zuhr prayer without sitting in between (the second and the third rak`at). When he finished the prayer he performed two prostrations (of Sahu) and then finished the prayer with Taslim.