http://www.berkshirehathaway.com/letters/2017ltr.pdf
https://www.ussif.org/files/GSIR_Review2018F.pdf
https://www.brookings.edu/research/the-national-security-grounds-for-investigating-musks-twitter-acquisition/?utm_campaign=brookings%20brief&utm_medium=email&utm_content=232621770&utm_source=hs_email
https://www.icij.org/investigations/uber-files/french-mps-to-investigate-ubers-lobbying-of-public-officials/