@article{10_4064_aa_2_1_47_79,
     author = {T Estermann},
     title = {On the representations of a number as a sum of squares},
     journal = {Acta Arithmetica},
     pages = {47--79},
     publisher = {mathdoc},
     volume = {2},
     number = {1},
     year = {1936},
     doi = {10.4064/aa-2-1-47-79},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-2-1-47-79/}
}