(25) باب التَّحَرِّي
It was narrated that Abdullah bin Ja'far said:
"The Messenger of Allah (ﷺ) said: 'Whoever has doubt during his prayer, let him prostrate twice after he has said the taslim'". (ID)
Reference (ID): Sunan an-Nasa'i 1248 (ID)
In-book reference (ID): Book 13, Hadith 70 (ID)
English translation (ID): Vol. 2, Book 13, Hadith 1249 (ID)