1. Stability of the travelling-salesman problem;Lront'ev;Zh. vych. Mat. i mat. Fiz,1975
2. Stability in combinatorial problems of choice;Leont'ev;Dokl. Akad. Nauk SSSR,1976
3. Stability in linear discrete problems;Leont'ev,1979
4. Stability in discrete optimal problems;Gordeev,1980
5. Bottle-neck optimization problems;Gordeev,1980