@article{RCM_2013_47_1_a3,
     author = {Herbert Due\~nas and Juan C. Garc{\'\i}a and Luis E. Garza},
     title = { Alejandro {Ram{\'\i}rez,}},
     journal = {Revista colombiana de matematicas},
     pages = {39--66},
     publisher = {mathdoc},
     volume = {47},
     number = {1},
     year = {2013},
     url = {http://geodesic.mathdoc.fr/item/RCM_2013_47_1_a3/}
}