Meetings for those involved in the use (or development) of GD systems in Germany are regularly given the opportunity to come together and discuss all aspects of the technique. The latest meeting was held in Freiberg in September 2019 and was well attended, as can be seen in the group photo of the delegates.
A copy of the program of the latest meeting can be found at
http://www.dge-homepage.de/gdoes/program_2019_freiberg.htm