| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Germania e Santa Sede. Le nunziature di Pacelli tra la grande guerra e la repubblica di Weimar | 978-88-15-03648-3 (88-15-03648-2) | 1992 |
| Hitler, Mussolini and the Vatican: Pope Pius XI and the Speech That Was Never Made | 978-0-7456-4488-2 (0-7456-4488-0) | 2011 |