@article{10_4153_CMB_2007_041_0,
     author = {Mej{\'\i}a, Israel Moreno},
     title = {On the {Image} of {Certain} {Extension} {Maps.} {I}},
     journal = {Canadian mathematical bulletin},
     pages = {427--433},
     year = {2007},
     volume = {50},
     number = {3},
     doi = {10.4153/CMB-2007-041-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-2007-041-0/}
}