Pier della Vigna. 2024. Letters in 5 Books: Critical Edition of the Oldest Systematic Collection, by Debora Riso. Introduction by Fulvio Delle Donne. Edited by Debora Riso. Miscellaneous. SHARE Books. https://www.fedoabooks.unina.it/index.php/fedoapress/catalog/book/978-88-98943-78-4.