When applying for positions in academia (I think the question is valid for economy as well) I add several documents to my application: cover letter/motivational letter, CV, publication list, PhD Certificate, Diploma, employers' references. As a PhD student and as a post-doc I have visited several courses that train soft skills like conflict management and are certified. These courses are offered by the university and provide a certificat and a supplement.
For any application, should I attach both documents (certificate and supplement) or only the certificate?
All in all my application start to get quite bloated (around 16 to 22 pages).