|Uncredited and undated photo from Google|
There aren't enough YouTube videos of this wonderful singer, and most are auf deutsch. Here is where you can learn about her from Wikipedia. (I suspect the German Wikipedia article has more information!)
Here is an extended audio track with Frau Köth as Musetta in La Boheme at the Deutsche Opera Berlin under Wilhelm Schüchter. Others in the cast include Dietrich Fischer-Dieskau and Rudolph Schock.
Lucia, auf deutsch:
Norina's aria from Don Pasquale, again auf deutsch, no conductor or orchestra credit given:
With the Blessed Fritz Wunderlich live in La Cenerentola, again auf deutsch: