@article{JCA_2011_18_3_JCA_2011_18_3_a6,
     author = {P. G\'ora and R. J. Stern},
     title = {Subdifferential {Analysis} of the {Van} der {Waerden} {Function}},
     journal = {Journal of convex analysis},
     pages = {699--705},
     publisher = {mathdoc},
     volume = {18},
     number = {3},
     year = {2011},
     url = {http://geodesic.mathdoc.fr/item/JCA_2011_18_3_JCA_2011_18_3_a6/}
}