@article{VMUMM_1988_3_a7,
     author = {S. V. Bolotin},
     title = {On the {Hill} determinant of a periodic orbit},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {30--34},
     publisher = {mathdoc},
     number = {3},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1988_3_a7/}
}