Gayle, Damien; Topping, Alexandra; Sample, Ian; Marsh, Sarah; Dodd, Vikram (13. 5. 2017). „NHS seeks to recover from global cyber-attack as security concerns resurface”. The Guardian. Pristupljeno 14. 5. 2017. »One NHS worker, who asked to remain anonymous, said the attack began at about 12.30pm and appeared to have been the result of phishing. 'The computers were affected after someone opened an email attachment.'«
