@article{JIS_2011__14_3_a1,
     author = {de Koninck, Jean-Marie and Doyon, Nicolas and Luca, Florian},
     title = {Powerful values of quadratic polynomials},
     journal = {Journal of integer sequences},
     publisher = {mathdoc},
     volume = {14},
     number = {3},
     year = {2011},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2011__14_3_a1/}
}