1. M. Jacob andG. C. Wick:Ann. of Phys.,7, 404 (1959), to which we refer as J. W.
2. A. A. Logunov, Nguyen Van Hieu andI. T. Todorov:Ann. of Phys.,31, 203 (1965), which also contains a complete list of references to earlier work in this field
3. L. Van Hove:High-Energy Physics and Elementary Particles (IAEA, Vienna, 1965), p. 179.
4. L. Van Hove:Proceedings of the International Symposium on Electron and Photon Interactions at High Energy, Hamburg (June 8–12, 196), p. 1.
5. Introductions to this field can be found inL. Van Hove:Theoretical Problems in Strong Interactions at High Energies, CERN report 65-22 (1965), in particular Ch. IV, andA. Bialas:Analyticity and High-Energy Scattering, Lectures at Ecole Internationale de la Physique des Particules Elémentaires, Herceg Novi (1965).