@article{IVM_2005_6_a1,
     author = {A. V. Aminova and N. A.-M. Aminov},
     title = {Fourth-order differential systems with a four-dimensional solvable symmetry group that does not contain the abelian subgroup $G_3$},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {12--27},
     publisher = {mathdoc},
     number = {6},
     year = {2005},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2005_6_a1/}
}