- D.N. Bessis, Yu.S. Ledyaev, R.B. Vinter, “Dualization of the Euler and Hamiltonian inclusions”, Nonlinear Analysis: Theory, Methods & Applications, 43, № 7, 2001, 861
- F.H. Clarke, “A proximal characterization of the reachable set”, Systems & Control Letters, 27, № 3, 1996, 195