Here you can find some useful links to internet sites with similar topics:
http://www.ifhb.de
Homepage by I.F.H.B. - Internationales Forum Historische Bürowelt

http://www.curta.de
Curta -Site by Jan Meyer

http://www.curta.ch
Beck's Typewriter, Schreibmaschinen-Museum

http://www.curta.org
American Curta-Site

http://www.vcalc.net/cu.htm
Curta-Site by Rick Furr