@article{GT_2007_11_2_a2,
     author = {Januszkiewicz, Tadeusz and \'Swi\k{a}tkowski, Jacek},
     title = {Filling invariants of systolic complexes and groups},
     journal = {Geometry & topology},
     pages = {727--758},
     publisher = {mathdoc},
     volume = {11},
     number = {2},
     year = {2007},
     doi = {10.2140/gt.2007.11.727},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/gt.2007.11.727/}
}