Not quite alone mate; just looking in prior to going home.
In response to your request, I get bugger all goggling Matthehner-Panek Pul-10 "as-is", 'coz there seems to be a typo in Ken's "Matthehner", maybe it should be Mattlener as that brings up what looks like your challenge and do away with the two names altogether and you get Reimar Horten's involvement in the project. seems like it has many variations and a few images showing the Pul-9, but titled Pul-10
Seems to me like he's got it, but for the typo!