Abstract
This paper is an attempt to study extensions of symmetric categorical groups from a structural point of view. Using in a systematic way bilimits in the 2-category of symmetric categorical groups, we develop a theory which closely follows the classical theory of abelian group extensions. The basic results are established for any proper class of extensions, and a cohomological classification is obtained for those extensions whose epi part has a categorical section.
Citation
D. Bourn. E. M. Vitale. "Extensions of symmetric cat-groups." Homology Homotopy Appl. 4 (1) 103 - 162, 2002.
