The purpose of this paper is to establish a theory of Baer invariants, associated to certain types of varieties of (pre)crossed modules, and to obtain a five term exact sequence and 'the basic theorem' of Stallings in this setting. Our method, which extends results of [4] and aspects of [9], gives a systematic treatment for several cases.
@article{urn:eudml:doc:39914,
title = {Baer invariants of crossed modules.},
journal = {Extracta Mathematicae},
volume = {6},
year = {1991},
pages = {35-38},
language = {en},
url = {http://dml.mathdoc.fr/item/urn:eudml:doc:39914}
}
Franco Fernández, Leoncio. Baer invariants of crossed modules.. Extracta Mathematicae, Tome 6 (1991) pp. 35-38. http://gdmltest.u-ga.fr/item/urn:eudml:doc:39914/