1. T. Carleman, Les Fonctions Quasi Analytiques, Gauther-Villarars, Paris (1926).
2. A. N. Tikhonov and V. Ya. Arsenin, Methods of Solving Incorrect Problems [in Russian], Nauka, Moscow (1979).
3. L. A. Aizenberg and N. N. Tarkhanov, ?The abstract Carleman formula,? Dokl. Akad. Nauk SSSR,298, No. 6, 1292?1295 (1988).
4. A. Alexiewicz and Z. Semadeni, ?Linear functional on two-norm spaces,? Stud. Math.,17, No. 2, 121?140 (1958).
5. S. Agmon, A. Douglis, and L. Nirenberg, ?Estimates near the boundary for solutions of elliptic partial differential equations satisfying general boundary conditions: I,? Commun. Pure Appl. Math.,12, 623?727 (1959).