https://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID4092831_code1752653.pdf?abstractid=4092831&mirid=1
http://www.cesifo-group.de/ifoHome/publications/working-papers/CESifoWP/CESifoWPdetails?wp_num=6430&CESifoWP.search=+
https://www.occrp.org/en/biometric-bribery-semlex/the-optimist-without-borders-inside-the-semlex-ceos-empire-of-influence