1. J. P.Aubin,Approximation of elliptic boundary-value problems, Wiley-Interscience (1972).
2. A. V. Balakrishnan,Filtering and control problems for partial differential equations, Proc. 2nd Kingston Conf. on Differential Games and Control Theory, Univ. of Rhode Island, Marcel Dekker, Inc., New York (1976).
3. A. V. Balakrishnan,Boundary control of Parabolic Equations: L-Q-R theory, Proc. Conf. on Theory of Nonlinear Equations, Sept. 1977, Akademie-Verlag, Berlin (1978).
4. R. Courant -D. Hilbert,Methods of Mathematical Physics, I, Interscience Pubs., John Wiley, New York (1953).
5. G.Doetsch,Introduction to the Theory and Application of the Laplace Transform, Springer-Verlag (1979).