@article{10_4064_aa_25_1_115_120,
     author = {J. Hsia},
     title = {On the representation of cyclotomic polynomials as sums of squares},
     journal = {Acta Arithmetica},
     pages = {115--120},
     publisher = {mathdoc},
     volume = {25},
     number = {1},
     year = {1973},
     doi = {10.4064/aa-25-1-115-120},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-25-1-115-120/}
}