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2. The Analytic S-matrix Cambridge University Press, p. 57. See also T. Kawai and H. P. Stapp;Eden;Publ. RIMS, Kyoto Univ.,1977
3. Crossing, Hermitian Analyticity, and the Connection between Spin and Statistics
4. Physical‐Region Discontinuity Equations for Many‐Particle Scattering Amplitudes. I
5. Structural Analysis of Collision Amplitudes;Stapp,1976