Riyad as-Salihin, Book 16, Hadith 1426 (In-Book)

'Aishah (May Allah be pleased with her) reported: The Messenger of Allah used to recite in his bowing and prostration: "Subbuhun Quddusun, Rabbul-mala'ikati war-ruh [You are the Most Glorious. The Most Holy. You the Rubb of the angels and of Jibril[Muslim].

وعنها أن رسول الله صلى الله عليه وسلم كان يقول في ركوعه وسجوده‏:‏ ‏ "‏سبوح قدوس رب الملائكة والروح‏" ‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏

sunnah.com