1. Gas prices for industrial consumers. Eurostat. http://ec.europa.eu/eurostat/.
2. The technical choices for the 12 MW Bio-SNG demonstration on the Netherlands,2013
3. Biomass gasifier – Gas conditioning and conversion;Skjøth-Rasmussen,2014
4. Bio-SNG – Demonstration of the production and utilization of synthetic natural gas (SNG) from solid biofuels. Specific Targeted Research or Innovation Project. TREN/05/FP6EN/S07.56632/019895. D 1.4 FINAL PROJECT REPORT. https://www.dbfz.de/web/fileadmin/user_upload/B_Kraftstoffe/Final_project_report_biomethan.pdf.
5. The SNG Technology Platform in Güssing, A Status report of Bio-SNG project. Paul Scherrer Institut. http://www.eee-info.net/cms/netautor/napro4/wrapper/media.php?id=%2C%2C%2C%2CZmlsZW5hbWU9YXJjaGl2ZSUzRCUyRjIwMDkuMDIuMTclMkYxMjM0ODg2NzE3LnBkZiZybj1CaW8tU05HJTIwVGVjaG5vbG9neSUyMGVuZ2xpc2NoLnBkZg%3D%3D.