1. M. A. Soloviev, Theor. Math. Phys., 121, 1377 (1999).
2. G. V. Efimov, Problems of Quantum Mechanics of Nonlocal Interactions [in Russian], Nauka, Moscow (1985).
3. I. M. Gelfand and G. E. Shilov, Generalized Functions [in Russian], Vol. 2, Functions and Generalized Function Spaces, Fizmatgiz, Moscow (1958); English transl., Acad. Press, New York (1968).
4. R. F. Streater and A. S. Wightman, PCT, Spin and Statistics and All That, Benjamin, New York (1964).
5. N. N. Bogoliubov, A. A. Logunov, A. I. Oksak, and I. T. Todorov, General Principles of Quantum Field Theory [in Russian], Nauka, Moscow (1987); English transl., Kluwer, Dordrecht (1990).