@article{10_4064_aa_36_3_297_313,
     author = {P. Tur\'an},
     title = {On a problem of {E.} {Landau}},
     journal = {Acta Arithmetica},
     pages = {297--313},
     publisher = {mathdoc},
     volume = {36},
     number = {3},
     year = {1980},
     doi = {10.4064/aa-36-3-297-313},
     language = {de},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-36-3-297-313/}
}