1. Araki, H.: Hamiltonian formalism and the canonical commutation relations in quantum field theory. J. Math. Phys.1, 492 (1960).
2. cf.Gelfand, I. M., andN. Y. Vilenkin: Generalized functions. Vol. 4, (last section). New York: Academic Press 1964.
3. Lew, I. S.: The structure of representations of the canonical commutation relations in quantum field theory. Thesis, Princeton University 1960 (unpublished).
4. Neumann, J. von: Die Eindeutigkeit der Schrödingerschen Operatoren. Math. Ann.32, 191 (1931).
5. Straumann, N.: A new proof of von Neumann's theorem concerning the uniqueness of the Schrödinger operators. Helv. Phys. Acta40, 518 (1967).