@article{JCA_2005_12_2_JCA_2005_12_2_a3,
     author = {A. Mielke},
     title = {Necessary and {Sufficient} {Conditions} for {Polyconvexity} of {Isotropic} {Functions}},
     journal = {Journal of convex analysis},
     pages = {291--314},
     publisher = {mathdoc},
     volume = {12},
     number = {2},
     year = {2005},
     url = {http://geodesic.mathdoc.fr/item/JCA_2005_12_2_JCA_2005_12_2_a3/}
}