@article{JGG_2012_16_2_JGG_2012_16_2_a9,
     author = {D. Kusar },
     title = {Eleven {Years} of {Testing} {Spatial} {Visualization} {Skills}},
     journal = {Journal for geometry and graphics},
     pages = {235--246},
     publisher = {mathdoc},
     volume = {16},
     number = {2},
     year = {2012},
     url = {http://geodesic.mathdoc.fr/item/JGG_2012_16_2_JGG_2012_16_2_a9/}
}