@article{QUE_1982_1982_1_a11,
     author = {Balc\'azar, Jos\'e Luis},
     title = {De c\'omo ciertos conjuntos no pueden ser {NP-completos.}},
     journal = {Q\"uestii\'o},
     pages = {239-260},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1982},
     language = {es},
     url = {http://geodesic.mathdoc.fr/item/QUE_1982_1982_1_a11/}
}