1. Jönsson O, Polman E, Jensen JK, Eklund R, Schyl H, Ivarsson S. Sustainable Gas enters the European Gas Distribution System. In: Jönsson, editor. World Gas Conference; June 1-5, 2003; Tokyo. Oslo, Norway: International Gas Union; 2003. p. 9.
2. Utvärdering av uppgraderingstekniker för biogas;Persson,2003
3. Wellinger A, Lindberg A. Biogas Upgrading and Utilisation. [Internet] IEA Bioenergy Task 24: Energy From Biological Conversion of Organic Waste; 2005 [cited January 2011]. Available from: http://www.biogasmax.eu/media/biogas_upgrading_and_utilisation__018031200_1011_24042007.pdf.
4. Wheless E, Pierce J. Siloxanes in Landfill and Digester Gas Update. [Internet] Whittier (Canada) and Long Beach (California): Los Angeles Country Sanitation Districts and SCS Energy; 2004 [cited January 2011]. Available from: http://www.scsengineers.com/Papers/Pierce_2004Siloxanes_Update_Paper.pdf.
5. Adding gas from biomass to the gas grid;Hagen,2001