- May 18, 2016,
*Holonomy of Locally Conformally Kähler Metrics*

Geometric structures related to Hermitian and almost Hermitian manifolds, Leibniz University, Hannover. - July 8, 2015,
*Homogeneous Clifford Structures on Riemannian Manifolds*,

Symposium on the Geometry and Topology of Manifolds, Pacific Institute for the Mathematical Sciences, Vancouver, Canada. - October 10, 2014,
*Homogeneous Almost Quaternion-Hermitian Manifolds*,

Spinorial Geometry and Analysis on Manifolds, Centre international de recontres mathématique, Luminy, France. - August 30, 2013,
*Homogeneous Clifford Structures*,

Anniversary Conference Faculty of Sciences -- 150 years, University of Bucharest, Romania. - April 18, 2012,
*Lowest Eigenvalue of the Dirac Operator on Kähler Manifolds and Special Holonomy*,

Workshop: Geometric Structures on Manifolds, Banff International Research Center , Banff, Canada. - August 29, 2011,
*On Formal Riemannian Metrics*,

The 10th International Workshop on Differential Geometry and its Applications,

Ovidius University, Constanta, Romania. - November 4, 2010,
*Limiting Kähler Manifolds for Kirchbergs Inequalities*,

Lie Theory and Complex Geometry, Philipps University, Marburg, Germany. - August 30, 2010,
*A Representation-Theoretical Proof of Branson's Classification of Elliptic Generalized Gradients*,

Differential Geometry and Its Applications 2010, Masaryk University, Brno, Czech Republic. - January 19, 2010,
*Geometric Description of Kähler Manifolds Carrying Kählerian Twistor Spinors*,

Journées Nancéiennes de Géométrie, Institut Élie Cartan, Université Henri-Poincaré, Nancy, France.

- June 7, 2016,
*On Toric Vaisman Manifolds*,

Research Seminar, Philipps University, Marburg. - March 6, 2014,
*Structures de Clifford homogènes*,

Seminar on Algebra, Topology and Geometry, University of Nice. - March 3, 2014,
*Structures de Clifford homogènes*,

Seminar on Analysis, Geometry and Topology, University Aix-Marseille. - June 6, 2013,
*Homogeneous Clifford structures*,

Kepler-Kolloquium, University of Regensburg. - December 5, 2012,
*Extremal Rank Homogeneous Clifford Structures*,

Geometry and Topology Oberseminar, University of Bielefeld. - April 26, 2012,
*Homogeneous Clifford Structures*,

Oberseminar Global Analysis, University of Regensburg. - December 7, 2011,
*Higher Rank Homogeneous Clifford Structures*,

Forschungsseminar, Humboldt Universität, Berlin. - May 18, 2011,
*Dirac Operators in Kähler Geometry*,

Spring School Index Theory, Graduiertenkolleg Regensburg, Hesselberg. - January 5, 2011,
*On Formal Riemannian Metrics*,

Differential Geometry Seminar, IMAR, Bucharest. - March 30, 2010,
*Special Classes of Spinors on Riemannian and Kähler Manifolds*,

Doctorands Seminar, Mathematics Research Unit, University of Luxemburg. - March 11, 2010,
*Die geometrische Beschreibung von Kählerschen Mannigfaltigkeiten die Kählersche Twistorspinoren zulassen*,

Faculty of Mathematics, Ruhr-University, Bochum. - January 28, 2010,
*The Geometric Description of Kähler Manifolds Carrying Kählerian Twistor Spinors*,

Differential Geometry Oberseminar, Institute of Differential Geometry, Leibniz University, Hannover - June 3, 2009,
*Kähler Manifolds Carrying Kählerian Twistor Spinors*,

Differential Geometry Seminar, IMAR, Bucharest. - May 26, 2009,
*Kählersche Mannigfaltigkeiten mit kleinstem Eigenwert des Dirac-Operators*,

Geometry Oberseminar, Faculty of Mathematics, LMU München. - April 30, 2009,
*Kählersche Mannigfaltigkeiten, die Kählersche Twistorspinoren zulassen*,

Differential Geometry Oberseminar, Institute of Mathematics, University of Regensburg - April 20, 2009,
*Kählersche Mannigfaltigkeiten mit kleinstem Eigenwert des Dirac-Operators*,

Differential Geometry Oberseminar, Department of Mathematics, University of Hamburg. - February 10, 2009,
*A Short Insight into Spin Geometry*, Outline as [pdf],

Blockseminar Graduiertenkolleg, Wermelskirchen. - September 10, 2008,
*Kato Constants and Ellipticity of Generalized Gradients*,

Differential Geometry Seminar, Institute of Mathematics Simion Stoilow of the Romanian Academy, Bucharest. - May 26, 2008,
*Ellipticity of Generalized Gradients*,

A. Besse Seminar, Centre de Mathématiques Laurent Schwartz, École Polytechnique, Paris. - February 13, 2008,
*Geodesics and Jacobi Vector Fields on Riemannian Manifolds*,

Blockseminar Graduiertenkolleg, Marienthal. - December 11, 2007,
*Introduction to Conformal Geometry*,

Geometry Seminar, Institute of Mathematics, University of Cologne. - June 27, 2007,
*The Space of Weitzenböck Formulas on a Riemannian Manifold*,

Differential Geometry Seminar, Institute of Mathematics Simion Stoilow of the Romanian Academy, Bucharest - March 27, 2007,
*On Curvature*, Physikal Motivation as [pdf],

Graduiertenkolleg Fellow Seminar, University of Cologne. - March 12, 2007,
*Weitzenböck Formulas in Geometry and Topology*[pdf],

Blockseminar Graduiertenkolleg, Bad Honnef. - November 28, 2006,
*Extremal Metrics on Sasakian Manifolds*,

Geometry Seminar, Institute of Mathematics, University of Cologne.

- September 13-17, 2010, Summer School
*Canonical Metrics on Kähler Manifolds*, Cologne

(organized together with Prof. G. Marinescu and Prof. U. Semmelmann).