@article{CMH_1945__18_138869,
     author = {R. Soudan},
     title = {Sur les polydromies des fonctions biharmoniques.},
     journal = {Commentarii mathematici Helvetici},
     pages = {52--58},
     publisher = {mathdoc},
     volume = {18},
     year = {1945},
     zbl = {0061.24001},
     url = {http://geodesic.mathdoc.fr/item/CMH_1945__18_138869/}
}