@article{1102734960, author = {Zuckerman, Martin M.}, title = {Choosing $l$-element subsets of $n$-element sets.}, journal = {Pacific J. Math.}, volume = {97}, number = {2}, year = {1981}, pages = { 247-250}, language = {en}, url = {http://dml.mathdoc.fr/item/1102734960} }
Zuckerman, Martin M. Choosing $l$-element subsets of $n$-element sets.. Pacific J. Math., Tome 97 (1981) no. 2, pp. 247-250. http://gdmltest.u-ga.fr/item/1102734960/