Affiliation for manuscript publication If I am among the co-authors of a manuscript which I worked on while I was in a Laboratory during my Erasmus Experience, should I be affiliated only with the Laboratory or also the University I regularly attend?
The easiest way to handle this is to use the "present address" option that most journals offer authors. You would list the laboratory where you did the work as your affiliation in the header, and list the university you regularly attend as your "present address" to show you're not there anymore.

On the other hand, if you continued to work on the paper at your university (for instance, if the research was carried out at the Erasmus lab, but written up after you returned home), then you'd list both as current affiliations.