Marcel van der Linden (1952) is Senior Fellow at the International Institute of Social History in Amsterdam. He is also a board member of the Internationale Marx-Engels-Stiftung (IMES), and co-responsible for the publication of the Marx-Engels Gesamtausgabe (MEGA).Gerald Hubmann (1962) is Secretary of the Internationale Marx-Engels-Stiftung (IMES), and coordinator and leading editor of the Marx-Engels Gesamtausgabe (MEGA) at the Berlin-Brandenburg Academy of Sciences.