Tyshkevich Sergey Viktorovich Russia Saratov State University, Russia, Saratov, Astrakhanskaya 83 Associate professorCandidate of physico-mathematical sciencestyszkiewicz@yandex.ru Author's articles One counterexample of shape-preserving approximation Everywhere divergence of Lagrange processes on the unit circle Extremal Rational Functions on Several Arcs of the Unit Circle with Zeros on these Arcs
