(Imām Bukhārī narrates): Hafs ibn 'Umar narrated to us, he said: Shu'bah narrated to us, from Qatādah, from Anas, that:

the Prophet ﷺ, Abū Bakr, and 'Umar, may Allāh be pleased with them both, used to open the prayer with "Al-hamdu lillāhi Rabbil-'ālamīn."