@article{GRSME_2000_2000_1_a6,
     author = {P\'erez Sanz, Antonio},
     title = {Los n\'umeros poligonales. {Una} caja de sorpresas con mucha historia.},
     journal = {La Gaceta de la Real Sociedad Matem\'atica Espa\~nola},
     pages = {331-337},
     publisher = {mathdoc},
     volume = {3},
     number = {2},
     year = {2000},
     language = {es},
     url = {http://geodesic.mathdoc.fr/item/GRSME_2000_2000_1_a6/}
}