@article{KauersKoutschanZeilberger09a,
 author = {Manuel Kauers and Christoph Koutschan and Doron Zeilberger},
 title = {Proof of {I}ra {G}essel's lattice path conjecture},
 journal = {Proceedings of the National Academy of Sciences},
 year = {2009},
 volume = {106},
 number = {28},
 pages = {11502--11505},
 isbn_issn = {ISSN 0027-8424},
 doi = {10.1073/pnas.0901678106},
 url = {http://www.koutschan.de/data/gessel/},
}