Metric Lie algebras with
maximal isotropic centre, (mit Martin Olbrich),
Math. Z. 246 (2004), 23-53.
Metric Lie algebras and
quadratic extensions, (mit Martin Olbrich), Transform. Groups 11 (2006), no. 1, 87--131.
New examples of indefinite
hyper-Kähler symmetric
spaces, (mit Martin Olbrich), J. Geom. Phys. 57 (2007), no. 8, 1697-1711.
Nilpotent metric Lie algebras
of small dimension, J. Lie Theory 17 (2007), no. 1, 41-61.
The classification problem for pseudo-Riemannian symmetric
spaces, (mit Martin Olbrich), in: Recent developments in pseudo-Riemannian Geometry (ed.
D. V. Alekseevsky and H. Baum), ESI Lectures in Mathematics and Physics,
EMS, 2008, 1-52.
Classification results for pseudo-Riemannian symmetric spaces, erscheint im Handbook of pseudo-Riemannian Geometry and Supersymmetry, IRMA Lectures in Mathematics and Theoretical Physics, EMS Publishing House.
