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2. Comodo fraud incident, January 2017. https://www.comodo.com/Comodo-Fraud-Incident-2011-03-23.html
3. DigiNotar SSL certificate hack amounts to cyberwar, says expert, January 2017. https://www.theguardian.com/technology/2011/sep/05/diginotar-certificate-hack-cyberwar
4. Yahoo hack: 1bn accounts compromised by biggest data breach in history, January 2017. https://www.theguardian.com/technology/2016/dec/14/yahoo-hack-security-of-one-billion-accounts-breached
5. Alliance, Z., et al.: Zigbee Specification (2006)