spectacle (1) prix (1) papier (1) plomb (1) effet (1) économie (1) classification (1) biocarburant (1) Petroleum (1) Paper (1) Oils and fats (1) Matter (1) Lead (1) Impact (1) Finance (1) Farm produce (1) Developing countries (1) Classification (1) Biomass energy (1) Classification (1) Classification (1) Finance (1) Utilization (1) Developed countries (1) Models (1)