1. Bourbaki, N.: Espaces vectoriels topologiques, Eléments de mathématique 25 and 28, Act. Sci. Ind. 1189 and 1229. Paris: Hermann 1953 and 1955.
2. Cook, J. M.: The mathematics of second quantization. Trans. Amer. Math. Soc.74, 222–245 (1953).
3. Dixmier, J.: Sur la relationi(PQ - QP) = 1. Comp. Math.13, 263–269 (1958).
4. Fock, V.: Konfigurationsraum und zweite Quantelung. Z. Physik75, 622–647 (1932).
5. Foiacş, C., L. Gehér, andB. Sz.-Nagy: On the permutability condition of quantum mechanics. Acta Sci. Math. (Szeged)21, 78–89 (1960).