@article{VM_2003_5_3_a1,
     author = {Izidor Hafner and Tomislav Zitko},
     title = {Mazes on surfaces},
     journal = {Visual Mathematics},
     year = {2003},
     volume = {5},
     number = {3},
     url = {http://geodesic.mathdoc.fr/item/VM_2003_5_3_a1/}
}