@article{05013499, title = {Counting upper interactions in Dyck paths.}, journal = {S\'eminaire Lotharingien de Combinatoire [electronic only]}, volume = {53}, year = {2005}, zbl = {1088.05011}, language = {en}, url = {http://dml.mathdoc.fr/item/05013499} }
Le Borgne, Yvan. Counting upper interactions in Dyck paths.. Séminaire Lotharingien de Combinatoire [electronic only], Tome 53 (2005) . http://gdmltest.u-ga.fr/item/05013499/