1. B.G. Boltyanskiy, “A method of tents in the theory of extremal problems” (in Russian), Uspekhi Matematicheskih Nauk 30 (1975) 3–55. Translated in Russian Mathematical Surveys 30 (3) (1975) 1–54.
2. V.F. Demyanov and L.N. Polyakova, “Minimization of a quasidifferentiable function on a quasidifferentiable set”, Zhurnal Vychislitel’noi Matematiki i Matematicheskoi Fiziki 20 (1980) 849–856. Translated in U.S.S.R. Computational Mathematics and Mathematical Physics 20 (1980) 34–43.
3. V.F. Demyanov and A.M. Rubinov, “On quasidifferentiable functionals”, Doklady Akademii Nauk SSSR 250 (1980) 21–25. Translated in Soviet Mathematics Doklady 21 (1980) 14–17.
4. V.F. Demyanov and A.M. Rubinov, “On some approaches to the non-smooth optimization problem” (in Russian) Ekonomika i Matematicheskie Metody 17 (1981) 1153–1174.
5. V.F. Demyanov and L.V. Vasiliev, Nondifferentiable optimization (in Russian) (Nauka, Moscow, 1981).