The following is not really a single poem but rather a collection of lines cited in Athenaeus, Plutarch and others and attributed to Cleobulina
Cleobulina fr. 3.1
“I have seen a man fashioning bronze on another man with fire
Fitting it so well that he joined them in the blood.
I saw a man stealing and deceiving violently—
To accomplish this with violence is the most just thing.
A donkey corpse struck me on the ear with its horny shin.”
ἄνδρ’ εἶδον πυρὶ χαλκὸν ἐπ’ ἀνέρι κολλήσαντα
οὕτω συγκόλλως ὥστε σύναιμα ποιεῖν.
ἄνδρ’ εἶδον κλέπτοντα καὶ ἐξαπατῶντα βιαίως,
καὶ τὸ βίαι ῥέξαι τοῦτο δικαιότατον.
κνήμηι νεκρὸς ὄνος με κερασφόρωι οὖας ἔκρουσεν·
These lines are poetic riddles: the first one, according to Athenaeus, is about using a cupping glass to draw blood to the surface of the skin) the last one is about a Phrygian flute (which was made from a donkey bone)