Musnad Ahmad 28:358

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, from al-Hakam, from Mujahid, from 'Abdullah ibn 'Amr, from the Prophet, peace and blessings of Allah be upon him, who said: "Whoever claims [to be the son of] someone other than his father, he shall never smell the fragrance of Paradise, and its fragrance is found from a distance of seventy years."