Comparison of methods to assess the sustainability of agricultural systems. A review Christian Bockstaller, Laurence Guichard, Olivier Keichinger, Philippe Girardin, Marie-Béatrice Galan and Gérard GaillardAgron. Sustain. Dev., 29 1 (2009) 223-235DOI: https://doi.org/10.1051/agro:2008058