Rotoli gemelli o elaborazioni successive? La relazione tra le due copie del terzo libro Sulla Retorica di Filodemo di Gadara

One of the two copies of Philodemus On rhetoric book III is qualified in the booktitle as 'hypomnematikon'. The same term returns in one of the two copies of book II and in the one extant copy of book I. While it was generally believed to indicate unifinished versions, David Blank took it as a generic term. But textvariants in book III confirm that the second bookroll copies the text of the 'hypomnematikon' with some changes due to Philodemus himself.