Authentic Supplication Number 85.

It is reported by way of Huthayfata  that he heard the Prophet  saying upon having bowed: Subhana rabbiyal `atheemi (97) three times, and upon having prostrated: Subhana rabbiyal-‘a`la (98) three times.

(97) Glory be to Allah The Magnificent.
(98) Glory be to Allah The Most High.

Reported by At-Tirmithi, Abu Dawood, An-Nisa’ee, and Ibn Majah. Al-Albani said it was sound due to its testimonials, and included this hadeeth in The Authentic of Good Sayings as #68.