Библиографическая ссылка:
Романов И.В., Шамаев А.С. Exact Controllability of the Distributed System, Governed by String Equation with Memory // Journal of Dynamical and Control Systems. 2013. V. 19. С. 611-623 http://link.springer.com/article/10.1007%2Fs10883-013-9199-y#page-2.