@article{JIS_2014__17_9_a1,
     author = {Duarte, Rui and de Oliveira, Ant\'onio Guedes},
     title = {A famous identity of {Haj\'os} in terms of sets},
     journal = {Journal of integer sequences},
     publisher = {mathdoc},
     volume = {17},
     number = {9},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2014__17_9_a1/}
}