Cetic.br. (2021). Executive Summary - Survey on the Internet service provider sector in Brazil: ICT Providers 2020.
Chicago-viite (17. p.)Cetic.br. Executive Summary - Survey on the Internet Service Provider Sector in Brazil: ICT Providers 2020. 2021.
MLA-viite (9. p.)Cetic.br. Executive Summary - Survey on the Internet Service Provider Sector in Brazil: ICT Providers 2020. 2021.
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