Musannaf Ibn Abi Shayba 3:2465

Ibn Idris narrated to us, from al-Hasan ibn ‘Amr, from Fudayl, from Sa‘id ibn Jubayr, that he saw a man praying when the iqamah for Asr was called. He said, "Does it please you that it be said, 'The son of so-and-so prayed six [rak'ahs]?'" He said: So I mentioned that to Ibrahim, and he said, "Prayer with the iqamah used to be disliked."