https://gdpr.report/news/2019/07/30/websites-are-making-less-money-since-gdpr/

https://www.europarl.europa.eu/RegData/etudes/STUD/2019/634447/EPRS_STU(2019)634447_EN.pdf

https://i.blackhat.com/USA-19/Thursday/us-19-Pavur-GDPArrrrr-Using-Privacy-Laws-To-Steal-Identities-wp.pdf

https://www.usitc.gov/publications/332/executive_briefings/gdpr_enforcement.pdf