@article{IM_1989__98_1_143740,
     author = {J.A. Rush},
     title = {A lower bound on packing density.},
     journal = {Inventiones mathematicae},
     pages = {499--510},
     publisher = {mathdoc},
     volume = {98},
     number = {1},
     year = {1989},
     zbl = {0659.10033},
     url = {http://geodesic.mathdoc.fr/item/IM_1989__98_1_143740/}
}