@article{VM_2014_16_1_a9,
     author = {Dejana Vojinovi\'c},
     title = {Celtic {Knots} and {Greatest} {Common} {Divisor}},
     journal = {Visual Mathematics},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/VM_2014_16_1_a9/}
}