From Sahih Bukhari (Hadith 4968):
Narrated Aisha:Allah's Messenger (ﷺ) used to say very often in bowing and prostration (during his prayers), Subhanka Allahumma Rabbana wa bihamdika; Allahumma ighfirli," according to the order of the Qur'an
Reference: Bukhari 4968