@article{JGG_2013_17_2_JGG_2013_17_2_a0,
     author = {M. Hagemann and D. Klawitter and B. Odehnal },
     title = {Curve {Flows} on {Ruled} {Surfaces}},
     journal = {Journal for geometry and graphics},
     pages = {129--14},
     publisher = {mathdoc},
     volume = {17},
     number = {2},
     year = {2013},
     url = {http://geodesic.mathdoc.fr/item/JGG_2013_17_2_JGG_2013_17_2_a0/}
}