The Book of Forgetfulness (In Prayer)
13/70. Chapter:
How to say the salam to one's right
Sunan an-Nasai
أَخْبَرَنَا الْحَسَنُ بْنُ مُحَمَّدٍ الزَّعْفَرَانِيُّ، عَنْ حَجَّاجٍ، قَالَ ابْنُ جُرَيْجٍ أَنْبَأَنَا عَمْرُو بْنُ يَحْيَى، عَنْ مُحَمَّدِ بْنِ يَحْيَى بْنِ حَبَّانَ، عَنْ عَمِّهِ، وَاسِعِ بْنِ حَبَّانَ، . أَنَّهُ سَأَلَ عَبْدَ اللَّهِ بْنَ عُمَرَ عَنْ صَلاَةِ، رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ اللَّهُ أَكْبَرُ كُلَّمَا وَضَعَ اللَّهُ أَكْبَرُ كُلَّمَا رَفَعَ ثُمَّ يَقُولُ " السَّلاَمُ عَلَيْكُمْ وَرَحْمَةُ اللَّهِ عَنْ يَمِينِهِ السَّلاَمُ عَلَيْكُمْ وَرَحْمَةُ اللَّهِ عَنْ يَسَارِهِ " .
It was narrated from Wasi' bin Habban that: He asked 'Abdullah bin 'Umar about the prayer of the Messenger of Allah (ﷺ). He said: "Allahu Akbar" every time he went down and "Allahu Akbar" every time he came up, then he said: "As-salamu 'alaykum wa rahmatullah (peace be upon you and the mercy of Allah) to his right and: As-salamu 'alaykum wa rahmatullah (peace be upon you and the mercy of Allah) to his left."
Reference : Sunan an-Nasa'i 1320In-book reference : Book 13, Hadith 142English translation : Vol. 2, Book 13, Hadith 1321