| 1 | BOSNIA AND HERZEGOVINA – RAILWAY REGULATORY BOARD |
| 2 | CROATIA – AGENCY FOR REGULATING THE MARKET OF RAILWAY SERVICES (ARTZU) |
| 3 | THE FORMER YUGOSLAV REPUBLIC OF MACEDONIA – REGULATORY AGENCY FOR RAILWAY |
| 4 | SERBIA – DIRECTORATE FOR RAILWAYS |
| 1 | BOSNIA AND HERZEGOVINA – RAILWAY REGULATORY BOARD |
| 2 | CROATIA – AGENCY FOR REGULATING THE MARKET OF RAILWAY SERVICES (ARTZU) |
| 3 | THE FORMER YUGOSLAV REPUBLIC OF MACEDONIA – REGULATORY AGENCY FOR RAILWAY |
| 4 | SERBIA – DIRECTORATE FOR RAILWAYS |