@article{10_4064_aa_5_4_407_415,
     author = {E. Cohen},
     title = {Arithmetical functions associated with arbitrary sets of integers},
     journal = {Acta Arithmetica},
     pages = {407--415},
     publisher = {mathdoc},
     volume = {5},
     number = {4},
     year = {1959},
     doi = {10.4064/aa-5-4-407-415},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-5-4-407-415/}
}