@article{10_4064_aa114_1_6,
     author = {Pierre Kaplan and Kenneth S. Williams},
     title = {On the number of representations of a
  positive integer by a binary quadratic form},
     journal = {Acta Arithmetica},
     pages = {87--98},
     publisher = {mathdoc},
     volume = {114},
     number = {1},
     year = {2004},
     doi = {10.4064/aa114-1-6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa114-1-6/}
}