Help with mystery artist

I’ve just entered this artist after searching extensively to try to confirm/fix spelling or find any evidence at all of the artists, individually or together, without success. So I’m crowd-sourcing. Anybody have ideas?

I’d link directly to my source, too, but the darn website doesn’t put the full search in its URL so you have to redo the search every time. :frowning:

Bertl Ing sounds weird, maybe Bert Ling, or just Bertling (surname) (German/swedish names)?

That’s possible, although they are both valid names.