@article{MOMA_1989__107_3_178417,
     author = {Wojciech Kucharz},
     title = {Sums of 2 n-th {Powers} of {Real} {Meromorphic} {Functions.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {131--136},
     publisher = {mathdoc},
     volume = {107},
     number = {3},
     year = {1989},
     zbl = {0691.12007},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1989__107_3_178417/}
}