| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Proceedings of the Second International Conference on Challenges in Higher Education & Research in the 21st Century: Organized by the Technical University of Sofia, June 2-5, 2004 Sozopol, Bulgaria | 978-954-58O-158-7 (954-58O-158-1) | 2004 | Nikolay Kolev |