@article{JSFU_2018_11_5_a1,
     author = {Oleg V. Kaptsov},
     title = {Intermediate systems and higher-order differential constraints},
     journal = {\v{Z}urnal Sibirskogo federalʹnogo universiteta. Matematika i fizika},
     pages = {550--560},
     publisher = {mathdoc},
     volume = {11},
     number = {5},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JSFU_2018_11_5_a1/}
}