@article{TAC_2000_7_a9,
     author = {G. Janelidze and G.M. Kelly},
     title = {Central extensions in {Mal'tsev} varieties},
     journal = {Theory and applications of categories},
     pages = {219--226},
     publisher = {mathdoc},
     volume = {7},
     year = {2000},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2000_7_a9/}
}