The Operetta Research Center has two offices, one in the Netherlands and one in Germany. You can send material to both addresses.
Our Amsterdam office is located at:
Guido ter Kuile
1077 BR Amsterdam, Netherlands
The Berlin office is situated at:
13403 Berlin, Germany
+49 (0)30 414 7812
Or you can use the contact us through the web form below. We will get back to you as soon as possible, and look forward to hearing from you.