źródło: https://www.theguardian.com/sport/2023/may/02/novak-djokovic-able-to-play-at-us-open-with-vaccine-mandate-set-to-end
źródło: https://www.theguardian.com/sport/2023/may/02/novak-djokovic-able-to-play-at-us-open-with-vaccine-mandate-set-to-end