Publications Thomas Schwager Volker Becker Thorsten Pöschel Coefficient of tangential restitution for viscoelastic spheres The European Physical Journal E, 27, 107-114 (2008) Volker Becker Thomas Schwager Thorsten Pöschel Coefficient of tangential restitution for the linear dashpot model Physical Review E, 77, 011304 (2008) Volker Becker Thorsten Pöschel Hourglass of constant weight Granular Matter 10, 231-232 (2008)