Abdullah bin 'Awn bin Artaban عبد الله بن عون بن أرطبان الخزار · The Book of Forgetfulness (In Prayer)

"The Messenger of Allah (ﷺ) led us in praying two rak'ahs, then he stood up and did not sit, and the people stood up with him. When he finished the prayer, and we were waiting for him to say the taslim, he said the takbir and prostrated twice while sitting, before the taslim. Then he said the taslim."

The Messenger of Allah (ﷺ) prostrated twice after the salam on the day of Dhul-Yadain.

"Whoever us not sure about his prayer, then let him estimate what is correct, then let him prostrate twice after he finished his prayer, while he is sitting."