8 Jul 2001 / 2001, in ``Dwarf Galaxies and their Environment'', 40th Graduiertenkolleg-Workshop, eds. K.S. de Boer, R.-J. Dettmar, & U. Klein (Bonn:Shaker Verlag), 41-44
10 Oct 2000 / 150 Years of Quantum Many-Body Theory, R. F. Bishop, K. A. Gernoth, and N. R. Walet, eds. (World Scientific, Singapore, 2001), pp. 203--211.