@article{JCA_2011_18_1_JCA_2011_18_1_a9,
     author = {N. Hadjisavvas and D. T. Luc},
     title = {Second-Order {Asymptotic} {Directions} of {Unbounded} {Sets} with {Application} to {Optimization}},
     journal = {Journal of convex analysis},
     pages = {181--202},
     publisher = {mathdoc},
     volume = {18},
     number = {1},
     year = {2011},
     url = {http://geodesic.mathdoc.fr/item/JCA_2011_18_1_JCA_2011_18_1_a9/}
}