@article{PMF_1898_9_1_a1,
     author = {Mertens, Fr.},
     title = {O przest\k{e}pno\'sci liczb e i \ensuremath{\pi}},
     journal = {Prace Matematyczno-Fizyczne},
     pages = {28--45},
     publisher = {mathdoc},
     volume = {9},
     number = {1},
     year = {1898},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/item/PMF_1898_9_1_a1/}
}