Williams H. What’s an Online Ad Worth? Blockchain Might Help with That // Wall Street Journal. 2018. June 18 // ; Harvey C. How Blockchain Technology Changes Marketing // Marketing Science Institute. 2018. May 1. // (для просмотра требуется регистрация); O’Reilly L. Big Advertisers Embrace Blockchain to Root Out Digital Spending Waste // Williams H. Wall Street Journal. 2018. June 18 // .