@article{DANMA_2020_492_a23,
     author = {Yu. L. Sachkov},
     title = {Periodic time-optimal controls on two-step free-nilpotent {Lie} groups},
     journal = {Doklady Rossijskoj akademii nauk. Matematika, informatika, processy upravleni\^a},
     pages = {108--111},
     publisher = {mathdoc},
     volume = {492},
     year = {2020},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DANMA_2020_492_a23/}
}