$N$-Reggeon vertex for generalized Veneziano models

The $N$-reggeon vertex is constructed for generalized dual resonance models. This vertex factorizes and has simple properties under cyclic permutations of the external reggeons. The construction goes through for both Bose and Fermi operators. As special cases, we obtain $N$-reggeon vertex of Lovelace for the ordinary Veneziano model and the $N$-reggeon amplitude for the Neveu–Schwarz model.