http://www.egmontinstitute.be/content/uploads/2019/03/SPB108.pdf?type=pdf
https://www.opendemocracy.net/democraciaabierta/cristina-flesher-fominaya-andrea-teti/espa%C3%B1a-el-holograma-como-protesta
https://feps-europe.eu/wp-content/uploads/2024/07/PP25-WEB_PP.pdf
https://www.lse.ac.uk/european-institute/Assets/Documents/LEQS-Discussion-Papers/LEQSPaper169.pdf