On closer look, an MDPI “special issue” is a completely virtual one. The papers are published when they are received so that they get a running volume and page number, and are just earmarked to belong to a “special issue”. Thus, e.g. the special issue referred to by Dr. Lorenzo Iorio, above, had its first papers published in an earlier volume than the last ones, as the publication of this “special issue” run over half a year. Thus page numberf of papers in a “special issue” ae not consecutive. The “special issue” is actually virtual, created by labeling a set of running published papers as belonging to an “issue” in addition to their running volume.
Incidentally, one notices at the same time that Dr. Iorio has over the last years publshed in journals and books of several publishers that apper in this and related blogs as predatory or vanity presses, in addition to the two MDPI journals:
Frontiers
http://scholarlyoa.com/2013/11/05/i-get-complaints-about-frontiers/
from which Nature Publishing Group has recently diatanced it although many sites still refer to their earlier paertnership plans which never were realized.
http://news.sciencemag.org/people-events/2015/05/open-access-publisher-sacks-31-editors-amid-fierce-row-over-independence
NOVA Science
http://scholarlyoa.com/2015/05/26/watch-out-for-publishers-with-nova-in-their-name/#more-5317
http://scholarlyoa.com/2014/04/08/a-list-of-print-on-demand-publishers-self-publishingvanity-presses-and-other-non-traditional-publishers-for-librarians-and-authors/
World Scientific/Singapore
http://fakeconferences.blogspot.fr/2014/03/spam-from-bogus-fake-junk-world.html
Definitly he is not a troll of MDPI, as someone suspected above:
https://en.wikipedia.org/wiki/Lorenzo_Iorio
http://digilander.libero.it/lorri/homepage_of_lorenzo_iorio.htm
This is no comment on the quality of his research which is entirely different from mine and which I am thus unqualizied to assess.
