Thanl you a lot. It is my last message, sorry for insisting.
As I can not directly link to a special survey page, I can not bring the respondents directly to an "external survey start page", not with a button nor with a hyperlink. So last solution is to propose an hyperlink
at the bottom of certain page linking to another anonymous EFS survey (composed with last questions). But then is that possible to integrate the LFDN in that hyperlink in order to recover it (and to have the same LFDN in survey 1 export and survey 2 export)?
If yes, how do you transfer the LFDN using URL parameter, I mean how do you write it down? I read the manual, and tried adding #lfdn# in the hyperlink linking to survey 2 BUT
I can not recover the LFDN in survey 2 (when I export data from both surveys, respondents' lfdn are different in survey 1 and in survey 2)
ex : http://ww3.unipark.de/uc/etude_regio...v_mpt1/?#lfdn#
thank you for your help...