Manipulation of Graphs, Algebras and Pictures. Essays Dedicated to Hans-Jörg Kreowski on the Occasion of His 60th Birthday Authors Frank Drewes Annegret Habel Berthold Hoffmann Detlef Plump DOI: https://doi.org/10.14279/tuj.eceasst.26.369 Downloads PDF Published 2010-04-04 Issue Vol. 26 (2010): Manipulation of Graphs, Algebras and Pictures Section Preface