@article{JGG_2013_17_2_JGG_2013_17_2_a9,
     author = {G. Maresch },
     title = {Spatial {Ability} -- {The} {Phases} of {Spatial} {Ability} {Research}},
     journal = {Journal for geometry and graphics},
     pages = {237--25},
     year = {2013},
     volume = {17},
     number = {2},
     url = {http://geodesic.mathdoc.fr/item/JGG_2013_17_2_JGG_2013_17_2_a9/}
}