| Author: | Van Dongen, H. R., 1920-2010 |
| Subject: | PS, Science fiction, Space colonies -- Fiction |
| Format: | Text |
| Date issued: | 2008 |
| Language: | English |
| Publisher: | Project Gutenberg, |
| Rights: | Public domain in the USA. |
| Download link: | Citadel [electronic resource] / H. R. Van Dongen |