Hi ALL!

I'd like to ask if anyone has any info (or knows of a place online where some is tucked away) on Emil Busch lenses. In particular I'm looking for info on larger than average Pezvals, but of course any catalogs are always educational. The only thing I found is the 1904 lens adds on Antique Cameras site - http://antiquecameras.net/petzvallens.html However, largest one I see in Petzval designs there is a Seris I 12.5in FL, which is just over 3in glass diameter... I know I've seen these lenses much larger before, so how does one go about researching them?

Thank you.