@article{TAC_2008_21_a8,
     author = {Ana Helena Roque},
     title = {Notes on effective descent and projectivity in quasivarieties of universal 
algebras},
     journal = {Theory and applications of categories},
     pages = {172--181},
     publisher = {mathdoc},
     volume = {21},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2008_21_a8/}
}