"is it possible to look for the exact text ' © 2011 - StampMedia -', then extract the name(s) behind this text and write them into a field?"
Yes, there are a few calcs to get you there. Try this one:
pos = Length ("© 2011 - StampMedia -" ) ;
Middle ( text ; pos + 1 ; Length ( text ) )
Thank you La retta, your solution seems to work fine!
Anyone who has an idea to get the title from the articles?