Question: Was Arrigo Boito the librettist for both Mefistofele and L'Orfeo?
Sentence (from "Mefistofele"): Mefistofele (] ) is an opera in a prologue, four acts and an epilogue, the only completed opera with music by the Italian composer-librettist Arrigo Boito (there are several completed operas for which he was librettist only).
Relevant evidence: Yes