1. A. S. Mendelev, in Abstracts of Intern. Conf. Theory of Approximation of Functions and Operators Dedicated to 80th Anniversary of S.B. Stechkin, Yekaterinburg, 2000 (UrGU, Yekaterinburg, 2000), pp. 103–104.
2. A. S. Mendelev and M. S. Plotnikov, in Abstracts of All-Russain Conf. Algorithmic Analysis of Ill-Posed Problems, Yekaterinburg, 1998 (UrGU, Yekaterinburg, 1998), p. 166.
3. A. G. Babenko, Tr. Inst. Mat. Mekh. UrO RAN 2, 34–41 (1992).
4. P. L. Chebyshev “Theory of Mechanisms Known As Parallelograms,” in Complete Works by P.L. Chebyshev, Vol. 2: Mathematical Analysis (Akad. Nauk SSSR, Moscow-Leningrad, 1947), pp. 23–51 [in Russian].
5. S. N. Bernstein, Extremal Properties of Polynomials (ONTI, Moscow, 1937) [in Russian].