1. Biofuels sources, biofuel policy, biofuel economy and global biofuel projections;Demirbas;Energy Convers Manage,2008
2. The future of anaerobic digestion and biogas utilization;Holm-Nielsen;Bioresour Technol,2009
3. Biogas upgrading technology overview;Beil,2012
4. Energimyndighet, Produktion och användning av biogas och rötrester år 2013; 2014 [in Swedish]. [last accessed 2015 Jan].
5. Vanciu GA, Miresashvili N. Biocars in Sweden, An emerging market. The case of Sweden. Bachelor Thesis in Economics; 2012 Jönköping University.