If you need an invitation letter to attend HAIS 2016, please, send and email to:
Francisco Martínez Álvarez (fmaralv@upo.es)
giving all the details related to your paper: Id, title, authors, affiliation and also including the proper information about where to send it.
Also, please say if you need only a scanned versión of the letter or if you need the original letter send it to you via mail.