Author: Nikolay Alexeevich Klyuzhev. Candidate of sciences in technics, professor, the Pskov branch of the St. Petersburg State Engineering-Economical University, Pskov, Russia
E-mail: klujev-33@yandex.ru
Phone: 577-044
Author: Maria Milanova Stamatova. Student, Plovdiv University “Paisii Hilendarski”, Department of Mathematics and Informatics, Plovdiv, Bulgaria
E-mail: matias123tz@abv.bg
E-mail: klujev-33@yandex.ru
Phone: 577-044
Author: Maria Milanova Stamatova. Student, Plovdiv University “Paisii Hilendarski”, Department of Mathematics and Informatics, Plovdiv, Bulgaria
E-mail: matias123tz@abv.bg