# nLab model structure on crossed complexes

Brown and Golasinski gave a model category structure on the category of crossed complexes in

• Ronald Brown and Marek Golasinski, A model structure for the homotopy theory of crossed complexes, Cahiers de Topologie et Géométrie Différentielle Catégoriques, 30 no. 1 (1989), p. 61-82 (pdf)

The key facts used here are that the category of crossed complexes is monoidal closed, and that there is a good interval object, essentially the groupoid $\mathbf I$ extended to be a crossed complex.

Notice that by other work of Brown-Higgins, crossed complexes are equivalent to strict globular omega-groupoids, and also to strict cubical omega-groupoids with connections. In fact the monoidal closed structure on crossed complexes is deduced from that on strict cubical omega-groupoids.