%0 Journal Article %A T. Everaert %A T. Van der Linden %T Baer invariants in semi-abelian categories I: General theory %J Theory and applications of categories %D 2004 %P 1-33 %V 12 %I mathdoc %U http://geodesic.mathdoc.fr/item/TAC_2004_12_a0/ %G en %F TAC_2004_12_a0