Sunan Abi Dawud, 885

Sa’d reported that he heard his father or his uncle say ; I witnessed the Prophet (ﷺ) while offering prayer. He used to stay in his bowing and his prostration as long as one uttera the words “Glory be to Allah and praise be to Him” three times

Rapporté par Sa’d رضي الله عنه : Il a entendu son père ou son oncle dire : J’ai vu le Prophète ﷺ en train de prier. Il restait incliné et prosterné aussi longtemps qu’il fallait pour dire trois fois : « Gloire à Allah et louange à Lui. »