@article{DAN_1958_119_5_a12,
     author = {A. P. Shapiro},
     title = {Characteristic polynomials of third order rational symmetric matrices},
     journal = {Doklady Akademii Nauk},
     pages = {890--892},
     year = {1958},
     volume = {119},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1958_119_5_a12/}
}