Szerencsits, M. , Weinberger, C. , Kuderna, M. , Feichtinger, F. , Erhart, E. , Maier, S.. "Biogas from Cover Crops and Field Residues: Effects on Soil, Water, Climate and Ecological Footprint". World Academy of Science, Engineering and Technology, Open Science Index 100, International Journal of Environmental and Ecological Engineering, (2015), 9(4), 413 - 416.