The Messenger of Allah ﷺ would not sleep until he had recited Alif Lam Mim al-Sajdah and "Blessed is He in whose hand is dominion, and He is over all things competent" [Mulk 67:1].
كان رسول الله ﷺ لا ينام حتى يقرأ ألم السجدة، و{تبرك الذي بيده الملك وهو على كل شيء قدير}
Tirmidhi (2892), Ahmad (14695), Bukhari in Adab al-Mufrad (1209), and Nasai in Amal al-Yawm wal-Layla (707-708) all narrated it through various routes from Layth bin Abu Salim, from Abu Zubayr, from Jabir, who mentioned it.Its chain contains Layth bin Abu Salim, who is daif, but he is corroborated by Mughira bin Muslim Khurasani, who is truthful, from Abu Zubayr. Bukhari narrated his version in Adab al-Mufrad (1207), and Nasai in Amal al-Yawm wal-Layla (706).A detailed discussion of this is found in the book al-Adiyah wal-Adhkar.