. . "Erdölmarkt." . . "Oligopolie." . . "International economic relations." . . "Aardolie." . . "Organisatie van Petroleum Exporterende Landen." . . "Petroleum industry and trade." . . "Wereldmarkt." . . "Buitenlandse handelspolitiek." . . "commerce économie internationale industrie pétrole." . . "Economia internacional" . . "Erdölpreis." . . "Pétrole Industrie et commerce." . . "Pétrole - Industrie et commerce." . "Indústria petroquímica" . . . . . . . . . . "The international oil market a case of trilateral oligopoly" . "The international oil market a case of trilateral oligopoly"@en . . . . . . . . . . "The international oil market : a case of trilateral oligopoly" . "The international oil market : a case of trilateral oligopoly"@en . . . . . . . . "The International oil market : a case of trilateral oligopoly" . . . . . . . . . . . . .