Global Ad Spend: Display Ads See Double-Digit Growth in Q1
https://www.nielsen.com/us/en/insights/article/2013/global-ad-spend-display-ads-see-double-digit-growth-in-q1/
https://www.nielsen.com/us/en/insights/article/2013/global-ad-spend-display-ads-see-double-digit-growth-in-q1/