Who knows Columbia "E" Series or Ethnic green labe

Hallo,
I was wandering whether somebody out there knows how to get or where to find access to the Columbia records catalogue of the "E" series, or ethnic series from the 1918-1920 era.These had green labels, one find them regulary offered on Ebay.They have recordings from all kind of countries.I have special interest in the Duch recordings of which i own a few.The interesting thing is that most of these were not issued in Holland itself.So I am very curious what the total list is of Dutch recordings out of these E series.
Thanks

Paul Smits