Musannaf Ibn Abi Shayba 3:2480

Yahya ibn Adam narrated to us, he said: Zuhayr narrated to us, he said: Abu Ishaq narrated to us, he said: I was beside Abdullah ibn Mughaffal while he was praying and reciting from Surah al-Nur. Then the mu'adhdhin performed the iqamah, so he bowed and prostrated. Then he sat and recited the tashahhud, then he stood up with the Imam and took up [the recitation] from where he had finished.