Di Fiore, Laura. The Invisibles: Political Police and Secret Agents in the Nineteenth-Century Mezzogiorno. Vol. 21. FedOAPress - Clio: Essays in History, Archaeology and Art History. SHARE Books, 2018. Accessed October 9, 2026. https://www.fedoabooks.unina.it/index.php/fedoapress/catalog/book/81.