Complex sentence: Henzen was a leading authority on Latin epigraphy, and with Theodor Mommsen and Giovanni Battista de Rossi, he was co-editor of the "Corpus Inscriptionum Latinarum".
Split into simpler sentences: Henzen was a leading authority on Latin epigraphy. With Theodor Mommsen and Giovanni Battista de Rossi, he was co-editor of the "Corpus Inscriptionum Latinarum".