Tome 30 (1989) no. 1

Sommaire

A constructive “Closed subgroup theorem” for localic groups and groupoids
p. 3-23
Peculiar behavior of connected locales
p. 25-43
Remarks on duality for Σ-groups. I. Products and coproducts
p. 45-59
A model structure for the homotopy theory of crossed complexes
p. 61-82
On the connectedness of some topological spaces
p. 83-91