Ali, ST., & Antoine, J.-P. (1989). Coherent states of the 1+1 dimensional Poincaré group - Square integrability and a relativistic Weyl transform. Institut Henri Poincare. Annales: Physique Theorique, 51(1), 23-44. https://hdl.handle.net/2078.5/24780 (Original work published 1989)