links
| Free System Projekt | Band in which Ruud is playing. Style: very retro Berlin School |
| Gert Emmens | website of Gert Emmens and his solomusic |
| Synthesizers.com | site of the Synthesizers.com Arrick modular synthesizer; Ruud is one of the few Dutchies to own one |
| Elektor Formant | site, dedicated to the Elektor Formant modular synth; Gert own's 2 Formants |
| Ed Unitsky | Artist from Belarus. Has designed many covers for progrockacts, and has designed the cover for the third Emmens & Heij album ''Journey'' |