1. Livelihoods and approximation of livestock systems to organic production standards in Villaflores, Chiapas, Mexico;Aguilar;AIA,2012
2. Sustainability of US organic beef and dairy production systems: soil, plant and cattle interactions;Aimee;Sustainability,2013
3. Silvopastoral systems and their contribution to the environment;Alonso;Cuban J. Agric. Sci.,2011
4. General Theory of the Systems;Bertalanffy,1976
5. Energy analysis of organic and conventional agricultural systems;Bertilsson,2008