1. Iagolnitzer, D., Stapp, H. P.: Commun. math. Phys.14, 15–55 (1969) and references quoted therein
2. Coster, J., Stapp, H. P.: J. Math. Phys.10, 371–396 (1969);11, 1441–1463 (1970);11, 2743–2763 (1970)
3. Bloxham, M. J. W., Olive, D. I., Polkinghorne, J. C.: J. Math. Phys.10, 494–502, 545–552, 553–561 (1969)
4. Stapp, H. P.: In: Structural analysis of collision amplitudes (Les Houches 1975 June Institute) (ed. R. Balian, D. Iagolnitzer), Amsterdam, New York, Oxford; North-Holland Publ. Co. 1976
5. Iagolnitzer, D.: In: TheS-matrix. Amsterdam, New York, Oxford; North-Holland Publ. Co., to be published