Musnad Ahmad 27:1357

'Affan narrated to us, Wahib narrated to us, Ayyub narrated to us, from Nafi', that Ibn 'Umar used to go early to the mosque on the day of Jumu'ah, and he would pray rak'ahs in which he would prolong the standing. When the Imam would depart, he would return to his house and pray two rak'ahs. And he said: "This is how the Messenger of Allah, peace and blessings of Allah be upon him, used to do."