@article{10_4064_aa117_4_3,
     author = {Jens Marklof},
     title = {Mean square value of exponential sums
 related to the representation of
 integers as sums of squares},
     journal = {Acta Arithmetica},
     pages = {353--370},
     publisher = {mathdoc},
     volume = {117},
     number = {4},
     year = {2005},
     doi = {10.4064/aa117-4-3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa117-4-3/}
}