@article{VM_2001_3_2_a9,
     author = {Robert J and Krawczyk },
     title = {More {Curved} {Spirolaterals}},
     journal = {Visual Mathematics},
     publisher = {mathdoc},
     volume = {3},
     number = {2},
     year = {2001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/VM_2001_3_2_a9/}
}