| Author: | Barton, George, 1866-1940 |
| Subject: | UB, Secret service, Spies |
| Format: | Text |
| Date issued: | 2018 |
| Language: | English |
| Publisher: | Project Gutenberg, |
| Rights: | Public domain in the USA. |
| Download link: | The World's Greatest Military Spies and Secret Service Agents [electronic resource] / George Barton |