(54) باب التَّسْبِيحِ بَعْدَ الْفَرَاغِ مِنَ الْوِتْرِ وَذِكْرِ الاِخْتِلاَفِ عَلَى سُفْيَانَ فِيهِ
It was narrated from Ibn Abdur-Rahman bin Abza from his father that:
The Messenger of Allah (ﷺ) used to recite in witr: Glorify the Name of Your Lord, the Most High;' and "Say: O you disbelievers!'; and 'Say: He is Allah, (the) One." And after he had said the salam, he would say: Subhanal-Malikil-Quddus (Glory be to the Sovereign, the Most Holy).
Reference: Sunan an-Nasa'i 1754
In-book reference: Book 20, Hadith 157
English translation: Vol. 2, Book 20, Hadith 1755