@article{10_1090_S0894_0347_2011_00707_8,
     author = {Bourgain, Jean and Fuchs, Elena},
     title = {A proof of the positive density conjecture for integer {Apollonian} circle packings},
     journal = {Journal of the American Mathematical Society},
     pages = {945--967},
     publisher = {mathdoc},
     volume = {24},
     number = {4},
     year = {2011},
     doi = {10.1090/S0894-0347-2011-00707-8},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-2011-00707-8/}
}