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Asim O. Barut, Ivan Muzinich, and David N. Williams, "Construction of Invariant Scattering Amplitudes for Arbitrary Spins and Analytic Continuation in Total Angular Momentum," Phys. Rev. 130, 442–457 (1963).
Copyright © (1963) by the American Physical Society
DOI: 10.1103/PhysRev.130.442