Where are Statistics physically stored in SQL Server?

Question

Where are the Statistics used by the Query Optimizer physically stored inside a SQL Server database file and the Buffer Pool?

More specifically, is there a way to figure out the pages used by statistics using DMVs and/or DBCC?

I own both SQL Server 2008 Internals and SQL Server Internals and Troubleshooting books and none of them talks about the physical structure of the statistics; if they do I haven't be able to find this information.