Thank you for all your help. I've done some searching on the internet also. Many of these articles contain information that is copied from one person to another and some of this copied information isn't correct. It could be the same way with the Artbibliography, but this particular person, Haake, has stated that she is the ONE who knows about Bert. I've tried contacting her, but she wasn't willing to share what she knows. She was an art student and I'm wondering if she wrote the entire bio.
I sure do appreciate you trying your contact. That was very nice of you.