nLab
blueprint

• Oliver Lorscheid, The geometry of blueprints. Part I: Algebraic background and scheme theory, arxiv/1103.1745; The geometry of blueprints. Part II: Tits-Weyl models of algebraic groups, arxiv/1201.1324; Blueprints - towards absolute arithmetic, arxiv/1204.3129
• Javier López Peña, Oliver Lorscheid, Projective geometry for blueprints, arxiv/1203.1665

Spectra of blueprints glue to blue schemes similarly like spectra of rings glue to algebraic schemes. Blue schemes interpolate between the usual schemes and schemes over $F_1$, i.e. absolute geometry.

• some speculations on application of Reineke’s theorem on quiver Grassmanians for the world of blue schemes and $F_1$-schemes: Lieven’s blog