Economics (3) Fertility (3) pauvreté (2) papier (2) modèle (2) migration humaine (2) réchauffement mondial (2) climat (2) Economic conditions (2) Dynamics (2) Global warming (2) Will (2) Urbanization (2) Twenty-first century (2) Respect (2) Reason (2) Poverty (2) Population (2) Persons (2) Paper (2) Neutrality (2) Natural disasters (2) Migrant agricultural laborers (2) Human beings (2) Immigrants (2) Finance (2) Example (2) Equality (2) Emigration and immigration (2) Demography (2)