@article{JIS_2009__12_2_a3, author = {La Haye, Ross}, title = {Binary relations on the power set of an $n$-element set}, journal = {Journal of integer sequences}, publisher = {mathdoc}, volume = {12}, number = {2}, year = {2009}, language = {en}, url = {http://geodesic.mathdoc.fr/item/JIS_2009__12_2_a3/} }