@article{TAC_1999_6_a4,
     author = {Robert Par\'e},
     title = {Contravariant {Functors} on {Finite} {Sets} and {Stirling} {Numbers}},
     journal = {Theory and applications of categories},
     pages = {65--76},
     year = {1999},
     volume = {6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_1999_6_a4/}
}