Palgrave Macmillan · St. Martin's Press
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| The Portuguese Columbus: Secret Agent of King John II | 978-0-312-07948-2 (0-312-07948-6) | 1992 |
| The Portuguese Columbus: Secret Agent of King John II | 978-0-333-56315-1 (0-333-56315-8) | 1992 |