Ibn Abi Mulaykah relates: Urwah told me, from Marwan, that Zayd bin Thabit (may Allah be pleased with him) said to him: What is the matter with you, that I see you reciting the short surahs of the Mufassal in the prayer? For I saw the Messenger of Allah (peace and blessings be upon him) reciting the two long surahs (al-tuwalayayn). I asked: What is meant by the two long surahs? He said: Surah al-A'raf and Surah Yunus.
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4795