Brian Doyle wrote:

I have aquired an E-31 Esztergom (Rubik 254) from hungary as a
restoration project. I would be interested in hearing from anyone with
any knowledge of this glider. Specifically looking for pilot reports,
flight manual, (or any literature) photos, specifically of the
instrument panel, as our ship is missing its panel. (We can translate
hungarian documents)
If anyone is interested in learning more about this project, I can
send photos of this ship. We are currently working on a web site to
document the progress of this restoration at esztergom.glider.us.

This is what I managed to find:
http://bauerj.fw.hu/vitorla/e31/index.html
These are scans from Gabor Jereb's "Hungarian sailplanes" book. A
short history about the metal sailplane family designed by Erno Rubik
(femgep1-6), some details and a 3 view drawing about E31 (311-3) and
finally some technical data (adat1-2).
Regards,

/Janos