@article{IIGUM_2011_4_2_a3,
     author = {I. L. Vasiliev and A. V. Ushakov},
     title = {Lagrangian relaxations for the nonlinear $p$-median problem},
     journal = {The Bulletin of Irkutsk State University. Series Mathematics},
     pages = {45--59},
     publisher = {mathdoc},
     volume = {4},
     number = {2},
     year = {2011},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IIGUM_2011_4_2_a3/}
}