[2] Three years later, he was placed at the head of the Oriental collection in the National Library of Parma, of which he was made chief librarian in 1876.
[3] Though himself a Catholic priest, he was an avowed philosemite who published historical, literary and scientific studies in various Jewish journals, including the Antologia Israelitica and the Vessillo Israelitico.
[2][4] Prior to 1860 Perreau had written on various subjects, but from then on he devoted himself exclusively to rabbinical Jewish literature.
[5] Among other works, Perreau published a polygraphic edition of the commentary of Immanuel of Rome on the Psalms (Parma, 1879–82), on Esther (1880), and on Lamentations (1881).
He also published the Ma'amar Gan 'Eden of Rabbi Ḥayyim Israel, in the Zunz Jubelschrift, and Oceano dello abbreviature e sigle ebraiche, caldaiche, rabbiniche, talmudiche, cabalistiche, geographiche, etc.