"Economics of sustainability" . "States and territories established in 1847" . "Waste" . "American colonization movement" . "Environmental social science concepts" . "Least developed countries" . "Member states of the African Union" . "Sustainability" . "West African countries" . "English-speaking countries and territories" . "1847 establishments in Liberia" . "Liberia" . "Economic Community of West African States" . "Republics" . "Environmentalism" . "Countries in Africa" . "Member states of the United Nations" .