@article{KJM_2005_28_a1,
     author = {Leopold Verstraelen},
     title = {A geometrical description of visual perception},
     journal = {Kragujevac Journal of Mathematics},
     pages = {7 },
     publisher = {mathdoc},
     volume = {28},
     year = {2005},
     zbl = {1120.91328},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/KJM_2005_28_a1/}
}