Weyl-Pedersen calculus for some semidirect products of nilpotent Lie   groups
  For certain nilpotent real Lie groups constructed as semidirect products, algebras of invariant differential operators on some coadjoint orbits are used in the study of boundedness properties of the Weyl-Pedersen calculus of their corresponding unitary irreducible representations. Our main result is applicable to all unitary irreducible representations of arbitrary 3-step nilpotent Lie groups. 
Ingrid Beltita, Daniel Beltita, Mihai Pascu
math.RT math.AP