[Boost-users] nearest neighbors search with boost

I just find out that boost supports nearest neighbor searching, will amazes me. However, I do not want just to use the nearest() method, I want to study it and understand it. Is there any relevant documentation, specifically on how NNS is performed in R-tree? Are the code files that implement this method visible to the user? I downloaded the latest .tar file. Thank you in advance, Georgios PS - Hello Boost world! :)