Hadith 790:54
Mu'tamir narrated to us, from Khalid, from Abu Qilabah, from Abu al-Muhallab, from Imran ibn Husayn, that the Prophet (peace and blessings of Allah be upon him) prayed three rak'ahs, then he performed the taslim. It was said to him [about that], so he stood up and prayed one rak'ah, then he performed the taslim. Then he prostrated two prostrations while he was sitting.
حدثنا معتمر، عن خالد، عن أبي قلابة، عن أبي المهلب، عن عمران بن حصين، أن النبي صلى الله عليه وسلم " صلى ثلاث ركعات، فسلم فقيل له: فقام فصلى ركعة فسلم، ثم سجد سجدتين وهو جالس "