As an innocent bystander my perception is that B-Rep modelling is 75% academically well known and 25% implementation specific black magic.

Academic works: Mäntylä: "Solid modeling" Faigin: "Curves and Surfaces for Computer-Aided Geometric Design" Stroud: "Boundary representation modeling techniques"

Implementations: Parasolid, Acis, OpenCascade.

From implementation point of it's CSG (i.e. implementing the boolean operations) that will be among the biggest hurdles and where most of the black art is.

I've been reading Boundary Representation Modelling Techniques by Ian Stroud. Not the most approachable book, and I haven't read nearly all of it, but I already found it very valuable.