@article{PA_2018_7_1_a6,
     author = {Qi Feng},
     title = {An improper integral, the beta function, the {Wallis} ratio, and the {Catalan} numbers},
     journal = {Problemy analiza},
     pages = {104--115},
     publisher = {mathdoc},
     volume = {7},
     number = {1},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PA_2018_7_1_a6/}
}