@article{TAC_2001_8_a5,
     author = {Lurdes Sousa},
     title = {On the pullback stability of a quotient map with respect to a closure 
operator},
     journal = {Theory and applications of categories},
     pages = {100--113},
     publisher = {mathdoc},
     volume = {8},
     year = {2001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2001_8_a5/}
}