Nielsen: Advertentiebestedingen VS dalen 12 procent
http://blog.nielsen.com/nielsenwire/wp-content/uploads/2009/06/2009-q1-ad-spending1.pdf
via: http://econsultancy.com/blog/3988-us-ad-spending-drops-12-in-q1-report
http://blog.nielsen.com/nielsenwire/wp-content/uploads/2009/06/2009-q1-ad-spending1.pdf
via: http://econsultancy.com/blog/3988-us-ad-spending-drops-12-in-q1-report