Musannaf Ibn Abi Shayba 3:223

Abu Bakr narrated to us, he said: Ibn ‘Ulayyah narrated to us, from Ibn ‘Awn, who said: Muhammad [Ibn Sirin] used to say: When he says, "Sami‘a Allahu liman hamidah" (Allah hears those who praise Him), the one behind him says, "Sami‘a Allahu liman hamidah, Allahumma Rabbana laka al-hamd" (Allah hears those who praise Him, O Allah, our Lord, to You is the praise).