1. Oehme, R.: Complex Angular Momentum in Elementary Particle Scattering. In: Strong Interactions and High Energy Physics, pp. 129–222. Ed. R. O. Moorhouse. Edinburgh-London: Oliver and Boyd 1964. This article is frequently referred to in the form (O, page number). It contains references in the literature prior to 1964 which we do not repeat here.
2. Oehme, R.: High Energy Scattering and Dispersion Theory in Dispersion Relations and their Connection with Causality, pp. 167–256. Ed. E. P. Wigner. New York: Academic Press 1964.
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5. Gribov, V. N., Pomeranchuk, I. Ya., Ter-Martirosyan, K. A.: Phys. Rev. 139, B 184 (1965); Polkinghorne, J. C.: preprint.