A.A. Martynyuk

A.A.Martynyuk is Professor at S.P.Timoshenko Institute of Mechanics, National Academy of Sciences of Ukraine, Kiev.

C.Cruz-Hernandez is Professor at Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (CICESE), Mexico.

A.G.Mazko is Professor at Institute of Mathematics, National Academy of Sciences of Ukraine, Kiev.