Musnad Abu Ya'la al-Mawsili 210:8

Ibrahim ibn al-Hajjaj narrated to us, Hammad ibn Salamah narrated to us, from Ubayd Allah ibn Umar, from Nafi’, from Ibn Umar, that Hafsa said: When the Messenger of Allah (peace and blessings of Allah be upon him) prayed Jumu'ah, he would enter her house and pray two rak'ahs.