@article{TAC_2005_14_a13,
     author = {Yves Diers},
     title = {Classification of concrete geometrical categories},
     journal = {Theory and applications of categories},
     pages = {310--327},
     year = {2005},
     volume = {14},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2005_14_a13/}
}