@article{JIS_2007__10_7_a1,
     author = {Schr\"oder, Joachim},
     title = {Generalized {Schr\"oder} numbers and the rotation principle},
     journal = {Journal of integer sequences},
     publisher = {mathdoc},
     volume = {10},
     number = {7},
     year = {2007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2007__10_7_a1/}
}