Musannaf Ibn Abi Shayba 33:1255

'Isa ibn Yunus narrated to us, from al-Awza'i, from Hassan ibn 'Atiyyah, who said: While a man was riding a donkey, it stumbled with him, so he said, "May it be ruined (ta'asat)." The companion of the right said, "It is not a good deed, so I shall write it." And the companion of the left said, "It is not a bad deed, so I shall write it." Then the companion of the left was called out to: "Whatever the companion of the right has left, write it down."