Published papers

• Higher symmetries of power of the Laplacian and rings of differential operators, with J.T. Stafford, Compositio Mathematica, 153 (2017), 678--716 (pdf).
• Radial components, prehomogeneous vector spaces, and rational Cherednik algebras, Int. Math. Res. Not. IMRN, 2009 no. 3 (2009), 462--511 (pdf).
  
• Differential Operators and Cohomology Groups on the Basic Affine Space, with J.T. Stafford, Studies in Lie Theory, Dedicated to A. Joseph, Progress in Math., 243, Birkhauser, 2006, 377--403 (pdf).
• Krull dimension of the enveloping algebra of a semisimple algebra,  Proc. Amer. Math. Soc.,  130 (2002), 3519--3523 (pdf).
• Invariant distributions supported on the nilpotent cone of a semisimple Lie algebra,  Trans. Amer. Math. Soc.,  353 (2001), 4189--4202 (pdf).
• Invariant differential operators on the tangent space of some symmetric spaces, with J.T. Stafford, Annales de l'Institut Fourier, 49 (1999), 1711--1741 (pdf). See below for an extended version.
• Differential operators on some nilpotent orbits, with J.T. Stafford, Representation Theory , Volume 3 (1999), 457--473 (pdf).
• Adjoint vector fields on the tangent space of semisimple symmetric spaces, with R. Ushirobira, Journal of Lie Theory, 9 (1999), 293--304 (pdf).
• Equivariant D-modules attached to nilpotent orbits in a semisimple Lie algebra, Transformation Groups, 3 (1998), 337--353 (pdf).
• Differential operators commuting with invariant functions, with J.T. Stafford, Comment. Math. Helv., 72 (1997), 426--433 (pdf).
• Semi-simplicity of invariant holonomic systems on a reductive Lie algebra, with J.T. Stafford, Amer. J. Math., 119 (1997), 1095--1117 (pdf), and Corrigendum (pdf).
• The kernel of an homomorphism of Harish-Chandra, with J.T. Stafford, Ann. Sci. Éc. Normale Sup., 29 (1996), 385--397 (pdf).
• Invariant Differential Operators and an Homomorphism of Harish-Chandra, with J.T. Stafford, J. Amer. Math. Soc., 8 (1995), 365--372 (pdf).
• Algebraic structure of multi-parameter quantum groups, with T.J. Hodges and M. Toro, Advances in Math., 126 (1997), 52--92 (pdf).
• Primitive ideals of Cq[SL(n)], with T.J. Hodges, J. Algebra, 168 (1994), 455--468 (pdf).
• Primitive ideals of Cq[SL(3)], with T.J. Hodges, Comm. Math. Phys., 156 (1993), 581--605 (pdf).
• The quantum coordinate ring of the special linear group, with J.T. Stafford, J. Pure and Applied Algebra, 86 (1993), 181--186 (pdf).
• Modules over the Sklyanin Algebra, with S.P. Smith, Bull. Soc. Math. France, 121 (1993), 35--90 (pdf).
• Some Properties of Non-commutative Regular Graded Rings, Glasgow Math J., 34 (1992), 277-300 (pdf).
• Rings of differential operators on classical rings of invariants, with J.T. Stafford, Mem. Amer. Math. Soc., 81, 1989 (pdf).

Notes and unpublished papers

• D-modules et distributions sphériques (le cas tangent), exposé au Groupe de Recherche "Analyse Harmonique Invariante sur les Espaces Symétriques Réductifs", novembre 2004 (pdf).
• Invariant differential operators on the tangent space of some symmetric spaces, with J.T. Stafford, long version, 1997 (pdf). See above for the published version. 
• Notes on equivariant D-modules, October 1997 (pdf).
• Differential operators on a reductive Lie algebra, Lectures given at the University of Washington, Seattle, 1995 (pdf).
• Orbite nilpotente minimale, with P. Tauvel, 1994 (pdf).
• Primitive ideals of the quantum group Cq[G], with T.J. Hodges, 1993 (pdf).

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