The Arrangement of Words
From LSJ
Οὐ χρὴ φέρειν τὰ πρόσθεν ἐν μνήμῃ κακά → Mala pristina haud oportet ferre in memoria → Du darfst nicht im Gedächtnis tragen früheres Leid
Wikipedia EN
Περὶ συνθέσεως ὀνομάτων, The Arrangement of Words, Lat. De Compositione Verborum, a treatise by Dionysius of Halicarnassus treating of the combination of words according to the different styles of oratory.