1. Hajek, O., Dynamical Systems in the Plane, London, 1968.
2. Filippov, V.V., Prostranstva reshenii obyknovennykh differentsial’nykh uravnenii (Solution Spaces of Ordinary Differential Equations), Moscow: Moskov. Gos. Univ., 1993.
3. Filippov, V.V., Topological Structure of Solution Spaces of Ordinary Differential Equations, Uspekhi Mat. Nauk, 1993, vol. 48, no. 1, pp. 103–154.
4. Filippov, V.V., Basic Topological Structures of the Theory of Ordinary Differential Equations, in Topology in Nonlinear Analysis, Banach Center publications, 1996, vol. 35, pp. 171–192.
5. Filippov, V.V., Basic Topological Structures of Ordinary Differential Equations, Dordrecht; Boston; London, 1998.