Page is a not externally linkable
-- Google AdSense
---- Bad Neighborhoods in Unauthorized Sites
Leonard0 - 7:53 pm on Oct 13, 2011 (gmt 0)Thread source:: http://www.webmasterworld.com/google_adsense/4373964.htm
If all the bad traffic is coming from one site you could block those referals in htaccess.
Check the Apache forum for posts like this one:
Blocking referer in htaccess [webmasterworld.com]
Brought to you by WebmasterWorld: http://www.webmasterworld.com