@article{JGG_2004_8_1_JGG_2004_8_1_a10,
     author = {G. Prieto Adanez and A. D. Velasco },
     title = {Training {Visualization} {Ability} by {Technical} {Drawing}},
     journal = {Journal for geometry and graphics},
     pages = {107--115},
     publisher = {mathdoc},
     volume = {8},
     number = {1},
     year = {2004},
     url = {http://geodesic.mathdoc.fr/item/JGG_2004_8_1_JGG_2004_8_1_a10/}
}