From Sahih Muslim (Hadith 2040):
Abdullah b. 'Umar, while describing the Nafl prayer of the Messenger of Allah (ﷺ), said:He did not observe (Nafl) prayer after Jumu'a till he went back and observed two rak'ahs in his house. Yahya said: I guess that I uttered these words (before Imam Malik) that he of course observed (them)
Reference: Muslim 2040