@article{JGG_2006_10_2_JGG_2006_10_2_a3,
     author = {J. Wallner },
     title = {On a {Problem} of {Elementary} {Differential} {Geometry} and the {Number} of its {Solutions}},
     journal = {Journal for geometry and graphics},
     pages = {155--16},
     publisher = {mathdoc},
     volume = {10},
     number = {2},
     year = {2006},
     url = {http://geodesic.mathdoc.fr/item/JGG_2006_10_2_JGG_2006_10_2_a3/}
}