@article{MS2_1986__58_166975,
     author = {Otto Marstrander},
     title = {On a problem of {Frobenius.}},
     journal = {Mathematica Scandinavica},
     pages = {161--175},
     publisher = {mathdoc},
     volume = {58},
     year = {1986},
     zbl = {0607.10038},
     url = {http://geodesic.mathdoc.fr/item/MS2_1986__58_166975/}
}