@article{JRAM_1981__325_152356,
     author = {L. Vanhecke and B.-Y. Chen},
     title = {Differential geometry of geodesic spheres.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {28--67},
     publisher = {mathdoc},
     volume = {325},
     year = {1981},
     zbl = {0503.53013},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1981__325_152356/}
}