@article{10_4064_ap_41_1_37_42,
     author = {Z. Bogucki and J. Zderkiewicz},
     title = {Sur la courbure des lignes de niveau dans la classe $S^c_{\ensuremath{\alpha}k}$ des fonctions convexes d'ordre \ensuremath{\alpha} et k-sym\'etriques},
     journal = {Annales Polonici Mathematici},
     pages = {37--42},
     publisher = {mathdoc},
     volume = {41},
     number = {1},
     year = {1983},
     doi = {10.4064/ap-41-1-37-42},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-41-1-37-42/}
}