@article{02186866, title = {A combinatorial derivation of the number of labeled forests.}, journal = {Journal of Integer Sequences [electronic only]}, volume = {6}, year = {2003}, zbl = {1064.05083}, language = {en}, url = {http://dml.mathdoc.fr/item/02186866} }
Callan, David. A combinatorial derivation of the number of labeled forests.. Journal of Integer Sequences [electronic only], Tome 6 (2003) . http://gdmltest.u-ga.fr/item/02186866/