Authors that need an invitation letter to attend the conference please, send and email (after paper acceptance) to Conference Secretariat (soco-cisis-iceute2021@deusto.es). Add all the details related to your paper (ID, title, authors, and affiliation) and also including the proper information about where to send it.
Additionally, please tell us if you need only a scanned version of the letter or if you need the original letter to be post to you via mail.