- "STAR-SHAPED MESOGENS: SYNTHETIC CONTROL OF LIQUID CRYSTAL SELF-ASSEMBLY", M. Lehmann, Institut de Chimie et Interfaces Mulhouse, 29. September 2005, Frankreich.

- "STAR-SHAPED MESOGENS: SYNTHETIC CONTROL OF MOLECULAR SELF-ASSEMBLY", M. Lehmann, Universidad de Concepción, August 2005, Concepción (Chile).

- "STAR-SHAPED MESOGENS: SYNTHETIC CONTROL OF LIQUID CRYSTAL SELF-ASSEMBLY", M. Lehmann, Université Libre de Bruxelles, 17. Juni 2005, Belgien.

- "SUPRAMOLECULAR ORDER OF STILBENOID DENDRONS: IMPORTANCE OF WEAK INTERACTIONS", M. Lehmann, H. Meier, S. Renker, A. Oehlhof, "International Conference on Research Trends in Science and Technology", 2005, Beirut (Libanon).

- "NEMATIC LC PHASES FROM SHAPE-PERSISTENT V-SHAPED MOLECULES WITH LATERAL ALKOXY CHAINS", M. Lehmann, J. Levin, "32. Arbeitstagung Flüssigkristalle", 2004, Halle (Germany).

- "STAR-SHAPED MESOGENS WITH A 1,3,5-BENZENE CORE AS NON-CONVENTIONAL COLUMNAR LIQUID CRYSTALS", M. Lehmann, R. I. Gearba, M. H. J. Koch , D. A. Ivanov, "7th European Conference on Liquid Crystals", 2003, Jaca (Spain).

- "STAR-SHAPED MESOGENS WITH A 1,3,5-BENZENE CORE AS NON-CONVENTIONAL COLUMNAR LIQUID CRYSTALS", M. Lehmann, R. I. Gearba, M. H. J. Koch , D. A. Ivanov, "31. Arbeitstagung Flüssigkristalle", 2003, Mainz (Germany).

- "HEXAAZATRINAPHTHALENES: INFLUENCE DES DIFFERENTS GROUPES CONNECTEURES SUR LES TRANSITIONS DE PHASES", M. Lehmann, G. Kestemont, J. Tant, Y. Geerts, M. Watson, R. I. Gearba, D. A. Ivanov, "Journées Discotiques", 2003, Bruxelles (Belgium).

- "COLUMNAR LIQUID CRYSTALS FORMED BY SEMI-FLEXIBLE STAR-SHAPED OLIGOBENZOATES", M. Lehmann, R. I. Gearba, M. H. J. Koch , D. A. Ivanov, "Dendrimer Soft Self-Assembly Systems (DENSOM)", 2003, York (England).