I have been doing a little research on Burdicks collection as I hope to see it the next time I visit my father who lives in Chelsea. In an article by George Vrechek, he states that cards have been removed for safekeeping. Some have also been removed for matting
. The Wagner and Plank, along with some R300s, have shared this fate. Notations have been left in their place as to why they are not there.
If they ever cared about the collection at all, I hope it was during the removal process.