@article{10_1090_S0894_0347_2011_00718_2,
     author = {Astala, Kari and Iwaniec, Tadeusz and Prause, Istv\~A{\textexclamdown}n and Saksman, Eero},
     title = {Burkholder integrals, {Morrey\^a€™s} problem and quasiconformal mappings},
     journal = {Journal of the American Mathematical Society},
     pages = {507--531},
     publisher = {mathdoc},
     volume = {25},
     number = {2},
     year = {2012},
     doi = {10.1090/S0894-0347-2011-00718-2},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-2011-00718-2/}
}