1. BP, Statistical Review of World Energy, 2008. .
2. Choren Industries, Germany, Optimized Fuels for Sustainable Transport OPTFUEL, A demonstration project within the European 7th Framework programme, 2009. .
3. European Union Project – BioDME – Production of DME from Biomass and utilisation as fuel for transport and for industrial use Project No TREN/FP7EN/218923, 2008. .
4. Process design of Synthetic Natural Gas (SNG) production using wood gasification
5. Seemann, MC. Methanation of biosyngas in a fluidized bed reactor, PhD thesis, ETH Zurich, Switzerland, 2006, Diss. ETH No. 16754.