1. Department of Agricultural, Environmental and Food Policy, Martin Luther University Halle Wittenberg, Von-Seckendorff-Platz 4, 06120 Halle (Saale), Germany
2. Department of Economics of Agricultural Sector, Institute of Agricultural Economics and Information, Mánesova 1453/75, 12000 Prague, Czech Republic
3. Institute of Food and Resource Economics, Rheinische Friedrich-Wilhelms-Universität Bonn, Meckenheimer Allee 174, 53115 Bonn, Germany