Specification doc error #22

In both version 2.3 and version 2.4 of the OpenRTB-API-Specification-XX.pdf file, a reference link has been invalid， you should remove it from the specification document.

it's the "COPPA Regulation Flag" section, in 2.3 version it's 7.1 and 2.4 is 7.5. Content is as follows:
"
Steve Bellovin, CTO of the FTC, argued for a standardized signaling protocol in a blog posted dated
January 2013:
http://techatftc.wordpress.com/2013/01/02/coppa-and-signaling
"
and the link "http://techatftc.wordpress.com/2013/01/02/coppa-and-signaling" is invalid now, the document has been removed.