no. 2
Properties of non-unitary zero mass induced representations of the Poincaré group on the space of tensor-valued functions
Annales de l'institut Henri Poincaré. Section A, Physique Théorique, Tome 17 (1972) no. 2, pp. 111-118 
@article{AIHPA_1972__17_2_111_0,
     author = {Barut, A. O. and Raczka, R.},
     title = {Properties of non-unitary zero mass induced representations of the {Poincar\'e} group on the space of tensor-valued functions},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {111--118},
     year = {1972},
     publisher = {Gauthier-Villars},
     volume = {17},
     number = {2},
     mrnumber = {325032},
     language = {en},
     url = {https://www.numdam.org/item/AIHPA_1972__17_2_111_0/}
}
TY  - JOUR
AU  - Barut, A. O.
AU  - Raczka, R.
TI  - Properties of non-unitary zero mass induced representations of the Poincaré group on the space of tensor-valued functions
JO  - Annales de l'institut Henri Poincaré. Section A, Physique Théorique
PY  - 1972
SP  - 111
EP  - 118
VL  - 17
IS  - 2
PB  - Gauthier-Villars
UR  - https://www.numdam.org/item/AIHPA_1972__17_2_111_0/
LA  - en
ID  - AIHPA_1972__17_2_111_0
ER  - 
%0 Journal Article
%A Barut, A. O.
%A Raczka, R.
%T Properties of non-unitary zero mass induced representations of the Poincaré group on the space of tensor-valued functions
%J Annales de l'institut Henri Poincaré. Section A, Physique Théorique
%D 1972
%P 111-118
%V 17
%N 2
%I Gauthier-Villars
%U https://www.numdam.org/item/AIHPA_1972__17_2_111_0/
%G en
%F AIHPA_1972__17_2_111_0
Barut, A. O.; Raczka, R. Properties of non-unitary zero mass induced representations of the Poincaré group on the space of tensor-valued functions. Annales de l'institut Henri Poincaré. Section A, Physique Théorique, Tome 17 (1972) no. 2, pp. 111-118. https://www.numdam.org/item/AIHPA_1972__17_2_111_0/

[1] R. Shaw, Nuovo Cim., vol. 37, 1965, p. 1086; J. Bertrand, Nuovo Cim., vol. 1 A, 1971, p. 1; L. Bracci, Pisa preprint (July 1971); S.N. Gupta, Proc. Phys. Soc., A, vol. 63, 1950, p. 691; K. Bleuler, Helv. Phys. Acta, vol. 23, 1950, p. 567; H.E. Moses, J. math. Phys., vol. 5, 1968, p. 16 and references therein; W. Langbein, Comm. Math. Phys., vol. 5, 1967, p. 73; S. Weinberg, Brandeis Lectures, vol. 2, 1964, p. 405 (Prentice-Hall, 1965); A.S. Wightman and L. Gårding, Ark. Fys., vol. 28, 1965, p. 129; F. Strocchi, Phys. Rev., vol. 162, 1967, p. 1429; H.P. Dürr and E. Rudolph, Nuovo Cim., vol. 65 A, 1970, p. 423. | MR

[2] G. Mackey, see Appendix in E. Segal, Mathematical Problems in Relativistic Physics, 1965. (M. I. T. Press, 1966).

[3] The extension of Imprimitivity Theorem for representations of Poincaré group in topological vector spaces allows us to give a classification of non-unitary representation. See M. Flato and D. Sternheimer, Proceedings of French-Swedish Colloquium on Mathematical Physics, Goteborg, 1971.

[4] E.P. Wigner, Annals of Mathematics, vol. 40, 1939, p. 149. | Zbl | JFM

[5] J.M.G. Fell, Acta Math., vol. 114, 1965, p. 267. | Zbl | MR

[6] R. Raczka, Theory of Unstable Particles. Part I : Relativistic Quantum Mechanics of Isolated Particles, preprint, University of Colorado, Boulder, 1971.