[boost] Doxygen and Boostbook

While looking at the Boostbook documentation, I couldn't find documentation about how Doxygen documentation is transformed into Boostbook. I think documentation that says how one doxygen special block is transformed to a boostbook element would be useful, as well as how to generate boostbook elements from special blocks not supported by doxygen. For example, I don't know how to define concepts in Doxygen. Is such documentation available somewhere?