Musnad Ahmad 30:1072

The Messenger of Allah, peace and blessings of Allah be upon him, said: "A man bought a piece of real estate from another man. The man who bought the real estate found a jar containing gold in his real estate. The one who bought the real estate said to him: 'Take your gold from me; I only bought the land from you, and I did not buy the gold from you.' And the one who sold the land said: 'I only sold you the land and what was in it.'" He said: "They sought judgment from a man. The one to whom they sought judgment said: 'Do either of you have children?' One of them said: 'I have a boy.' The other said: 'I have a girl.' He said: 'Marry the boy to the girl, and spend on yourselves from it, and give charity.'"