1. E. Angelopolous, M. Laoues, Rev. Math. Phys. 10 (3) (1998) 271–299.
2. T.P. Branson, J. Funct. Anal. 74 (1987) 199–291.
3. V.K. Dobrev, G. Mack, V.B. Petkova, S.G. Petrova and I.T. Todorov, Harmonic Analysis on the n-Dimensional Lorentz Group and Its Applications to Conformal Quantum Field Theory, Lecture Notes in Physics, 63, (Springer-Verlag, Berlin-Heidelberg-New York, 1977), pp. 45–56.
4. G. Folland, Harmonic Analysis in Phase Space (Princeton University Press, Princeton, 1989).
5. K.C. Hannabuss, Math. Proc. Camb. Phil. Soc. 70 (1971) 283–299.