@article{10_4007_annals_2012_175_3_14,
     author = {Hugo Duminil-Copin and Stanislav Smirnov},
     title = {The connective constant of the honeycomb lattice equals $\sqrt{2+\sqrt 2}$},
     journal = {Annals of mathematics},
     pages = {1653--1665},
     publisher = {mathdoc},
     volume = {175},
     number = {3},
     year = {2012},
     doi = {10.4007/annals.2012.175.3.14},
     mrnumber = {2912714},
     zbl = {06051279},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4007/annals.2012.175.3.14/}
}