@article{10_4064_aa_58_2_169_172,
     author = {Imre Ruzsa},
     title = {The density of the set of sums},
     journal = {Acta Arithmetica},
     pages = {169--172},
     publisher = {mathdoc},
     volume = {58},
     number = {2},
     year = {1991},
     doi = {10.4064/aa-58-2-169-172},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-58-2-169-172/}
}