Papers and Preprints


  1. Linkssymmetrische Algebren und linkssymmetrische Strukturen auf Lie-Algebren,
    Bonner Mathematische Schriften 244, 1-65 (1993).

  2. Left-symmetric structures on simple modular Lie algebras,
    Journal of Algebra 169, Issue 1, 112-138 (1994).

  3. Modules for certain Lie algebras of maximal class, with F. Grunewald.
    Journal of Pure and Applied Algebra 99, Issue 3, 239-254 (1995).

  4. Left-invariant affine structures on reductive Lie groups,
    Journal of Algebra 181, Issue 3, 884-902 (1996).

  5. Affine structures on nilmanifolds,
    International Journal of Mathematics 7, Issue 5, 599-616 (1996).

  6. Etale affine representations of Lie groups,
    Geometry and Representation Theory of Real and p-adic Groups,
    Progress in Mathematics 158, 35-44 (1998).

  7. A refinement of Ado's theorem,
    Archiv der Mathematik 70, Issue 2, 118-127 (1998).

  8. Simple left-symmetric algebras with solvable Lie algebra,
    Manuscripta Mathematica 95, Issue 3, 397-411 (1998).

  9. Degenerations of nilpotent Lie algebras,
    Journal of Lie Theory 9, Issue 1, 193-202 (1999).

  10. Classification of orbit closures of 4--dimensional complex Lie algebras, with C. Steinhoff.
    Journal of Algebra 214, Issue 2, 729-739 (1999).

  11. Left-invariant affine structures on nilpotent Lie groups,
    Habilitation, Düsseldorf, 1-83 (1999).

  12. Estimates on binomial sums of partition functions,
    Manuscripta mathematica 103, Issue 4, 435-446 (2000).

  13. Affine cohomology classes for filiform Lie algebras,
    Contemporary Mathematics 262, 159-170 (2000).

  14. Lie algebra prederivations and strongly nilpotent Lie algebras,
    Communications in Algebra 30, Issue 7, 3157-3175 (2002).

  15. Sur les dégénérations d'algèbres de Lie,
    Report, 1-10 (2003).

  16. Cohomology of groups with applications to number theory,
    1-71, Lecture Notes 2004.

  17. Lie-Algebra Kohomologie,
    1-47, Lecture Notes 2005.

  18. Degenerations of 7-dimensional nilpotent Lie algebras,
    Communications in Algebra 33, Issue 4, 1259-1277 (2005).

  19. The Auslander conjecture for NIL-affine crystallographic groups, with K. Dekimpe and S. Deschamps,
    Mathematische Annalen 332, Issue 1, 161-176 (2005).

  20. On the matrix equation XA-AX=X^p,
    Linear Algebra and its Applications 404, 147-165 (2005).

  21. Characteristically nilpotent Lie algebras and symplectic structures,
    Forum Mathematicum 18, Issue 5, 769-787 (2006).

  22. Novikov structures on solvable Lie algebras, with K. Dekimpe,
    Journal of Geometry and Physics 56, Issue 9, 1837-1855 (2006).

  23. A remark on an inequality for the prime counting function,
    Mathematical Inequalities & Applications 10, Issue 1, 9-13 (2007).

  24. Left-symmetric algebras, or pre-Lie algebras in geometry and physics,
    Central European Journal of Mathematics 4, Issue 3, 323-357 (2006).

  25. Classical r-matrices and Novikov algebras,
    Geometriae Dedicata 122, Issue 1, 145-157 (2006).

  26. Degenerations and contractions of Lie algebras and algebraic groups,
    Oberwolfach Reports 3, Issue 1, 119-186 (2006).

  27. Analytische Zahlentheorie,
    1-109, Lecture Notes 2006.

  28. Lie Algebren und Darstellungstheorie,
    1-88, Lecture Notes 2006.

  29. Minimal faithful representations of reductive Lie algebras, with W. Moens,
    Archiv der Mathematik 89, Issue 6, 513-523 (2007).

  30. Cryptography,
    1-75, Lecture Notes 2007.

  31. Contractions of Lie algebras and algebraic groups,
    Archivum Mathematicum 43, Issue 5, 321-332 (2007).

  32. Novikov algebras and Novikov structures on Lie algebras, with K. Dekimpe and K. Vercammen,
    Linear Algebra and its Applications 429, Issue 1, 31-41 (2008).

  33. Affine actions on nilpotent Lie groups, with K. Dekimpe and S. Deschamps,
    Forum Mathematicum 21, Issue 5, 921-934 (2009).

  34. LR-algebras, with K. Dekimpe and S. Deschamps,
    New Developments in Lie Theory and Geometry, Amer. Math. Soc., Providence, RI,
    Contemporary Mathematics 491, 125-140 (2009).

  35. Computing faithful representations for nilpotent Lie algebras, with B. Eick and W. A. de Graaf,
    Journal of Algebra, Vol. 322, Issue 3, 602-612 (2009).

  36. Degenerations of pre-Lie algebras, with T. Benes,
    Journal of Mathematical Physics 50, Issue 11, 112102, 9 pp. (2009).

  37. Commutative Algebra,
    1-87, Lecture Notes 2009.

  38. Complete LR-structures on solvable Lie algebras, with K. Dekimpe and K. Vercammen,
    Journal of Group Theory 13, Issue 5, 703-719 (2010).

  39. Abelian ideals of maximal dimension for solvable Lie algebras, with M. Ceballos,
    Journal of Lie Theory 22, Issue 3, 741-756 (2012).

  40. Faithful Lie algebra modules and quotients of the universal enveloping algebra, with W. Moens,
    Journal of Algebra, Vol. 325, Issue 1, 440-460 (2011).

  41. Affine actions on Lie groups and post-Lie algebra structures, with K. Dekimpe and K. Vercammen,
    Linear Algebra and its Applications 437, Issue 5, 1250-1263 (2012).

  42. Classification of Novikov algebras, with W. A. de Graaf,
    Applicable Algebra in Engineering, Communication and Computing, Vol. 24, Issue 1, 1-15 (2013).

  43. Algebra im Überblick,
    1-87, Lecture Notes 2011.

  44. Post-Lie algebra structures and generalized derivations of semisimple Lie algebras, with K. Dekimpe,
    Moscow Mathematical Journal, Vol. 13, Issue 1, 1-18 (2013).

  45. Periodic derivations and prederivations of Lie algebras, with W. Moens,
    Journal of Algebra, Vol. 357, 208-221 (2012).

  46. Classification of orbit closures in the variety of 3-dimensional Novikov algebras, with T. Benes,
    Journal of Algebra and Its Applications, Vol. 13, Issue 02, 1350081, 33 pp. (2014).

  47. Algebraische Zahlentheorie,
    1-113, Lecture Notes 2013.

  48. Derived length and nildecomposable Lie algebras,
    Proceedings of the 13th International Symphosium of Mathematics and its Applications 2012,
    Scientific Buletin of the "Politehnica" University of Timisoara, 15-24 (2013). ISSN 1224-6069.

  49. Derivation double Lie algebras,
    Journal of Algebra and Its Applications, Vol. 15, Issue 06, 17 pp. (2016).

  50. Jacobi-Jordan algebras, with A. Fialowski,
    Linear Algebra and its Applications 459, 586-594 (2014).

  51. Post-Lie algebra structures on pairs of Lie algebras, with K. Dekimpe,
    Journal of Algebra, Vol. 464, 226-245 (2016).

  52. Commutative post-Lie algebra structures on Lie algebras, with W. A. Moens,
    Journal of Algebra, Vol. 467, 183-201 (2016).

  53. Étale representations for reductive algebraic groups with one-dimensional center, with W. Globke,
    Journal of Algebra, Vol. 487, 200-216 (2017).

  54. Group Theory,
    1-85, Lecture Notes 2017.

  55. Almost inner derivations of Lie algebras, with K. Dekimpe, and B. Verbeke,
    To appear in Journal of Algebra and Its Applications (2017).

  56. Étale representations for reductive algebraic groups with factors Sp(n) or SO(n), with W. Globke, and A. Minchenko
    Preprint (2017).

  57. Commutative post-Lie algebra structures and linear equations for nilpotent Lie algebras, with K. Dekimpe, and W. A. Moens,
    Preprint (2017).