I want to know the answer to the following question:
Which country were the researchers located in?
All the background I'm provided with is that "Both Krasner and Schroeder built upon the work performed by Eberhard F. Zwicker in the areas of tuning and masking of critical bands, that in turn built on the fundamental research in the area from Bell Labs of Harvey Fletcher and his collaborators.". Is that enough to answer the question?