Pullbacks of Crossed Modules and cat1-Groups

In this paper, wer define the pullback cat1-groups and we showed that the category of bullback cat1-group is equivalent to the category of pullback crossed modules. 1991 A. M. S. C.: 13D99, 16A99, 17B99, 18D35.

Pullbacks of Crossed Modules and cat1-Groups

In this paper, wer define the pullback cat1-groups and we showed that the category of bullback cat1-group is equivalent to the category of pullback crossed modules. 1991 A. M. S. C.: 13D99, 16A99, 17B99, 18D35.