vallée (2) fleuve (2) recherche (2) région (2) site archéologique (2) gestion (2) combustible (2) environnement (2) abords (agglomération) (2) Case (2) Area (2) Antiquities, Prehistoric (2) Exploitation (2) Area (2) Steppes (2) Societies (2) Research (2) Raw materials (2) Occupations (2) Nature and nurture (2) Natural resources (2) Management (2) Prehistoric peoples (2) Human beings (2) Grammar, Comparative and general--Case (2) Fuel (2) Euthenics (2) Ecology (2) Comprehension (2) Case (2)