@article{JGG_2015_19_2_JGG_2015_19_2_a8,
     author = {B. Herrera and A. Samper },
     title = {Definition and {Calculation} of an {Eight-Centered} {Oval} which is {Quasi-Equivalent} to the {Ellipse}},
     journal = {Journal for geometry and graphics},
     pages = {257--268},
     publisher = {mathdoc},
     volume = {19},
     number = {2},
     year = {2015},
     url = {http://geodesic.mathdoc.fr/item/JGG_2015_19_2_JGG_2015_19_2_a8/}
}