Musnad Abu Ya'la al-Mawsili 129:143

On the authority of Anas, he said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "I entered Paradise and saw a palace of gold. I said: 'For whom is this?' They said: 'For a young man from Quraysh.' I thought that it was me, so I said: 'For whom?' It was said: 'For Umar ibn al-Khattab.'"