@article{ETNA_2013__40__a2,
     author = {Hakula, Harri and Rasila, Antti and Vuorinen, Matti},
     title = {Computation of exterior moduli of quadrilaterals},
     journal = {Electronic transactions on numerical analysis},
     pages = {436--451},
     publisher = {mathdoc},
     volume = {40},
     year = {2013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_2013__40__a2/}
}