“…Alternatively, they used a similar un-certified product as counterfactual (De Roest and Menghi, 2000;Gerz and Dupont, 2006;Hauwuy et al, 2006) and tracked its divergent evolution since the creation of the GI (Vakoufaris, 2010). Previous studies were either based on census data at the level of administrative units (Hauwuy et al, 2006;Hirczak and Mollard, 2004) or on supply chains (Biénabe, 2009;Emperaire et al, 2012;Vakoufaris, 2010). In some cases, they included farm-level interviews (Bowen and Zapata, 2009;De Roest and Menghi, 2000;Quetier et al, 2005).…”