Claus H Willenberg and Edward Lapolka

Am still looking for magazine from earlier post but am now looking for information on two stained glass painters.

I contacted the SGAA office and they tell me the "index" lists the following info about them:
Willenberg, Claus H. 957 A new installation for the Centennial

Lapolka, Edward 88, 306, 388, 1008 all are references to the Tariff War articles.

I don't know how to find copies of the articles and hope someone out there knows about/has copies of magazines with these articles. Below I will copy my original query to SGAA so you will know why I am looking.

"I'm wondering if someone could guide me in locating information about painters of stained glass.

I am trying to help an 83 years old retired artist recall information about some painted medallions he has.

Robert Donovan was a stained glass artist in California from the 1940s to 1975. He had a large studio in Southern California (did 3000 sq ft of glass for Stauffer Chapel - Pepperdine University). He employed several people to help create his art including painters of stained glass.

He has several boxes of painted medallions and other, one of a kind , painted pieces that we are trying to keep from being lost forever when he is gone.

The problem is he remembers names - not spellings - he remembers general information - not all details...
I would like to find information about the artists to tie them in with the pieces while Bob is still able to help authenticate the work.

He has pieces he remembers to be by an Polish artist - LAPOKA - (his phonetic spelling) which Bob says were created in about the 1920s... he says "Lapoka" probably died in the late 1940s.

Bob has many medallions painted by "his painter". His phonetic spelling of the artist's name is - Claus Willenberg - He says "Claus" was about 80 in the 1960's when he was painting for Donovan's Studio."

Any help with information on these painters would be greatly appreciated.