I spend a very busy morning attempting to locate the publication of the Mithraeum in Vulci, in Etruria. My search was rewarded, after around 3 hours persistence, by discovering that it was online! It was certainly impossible to buy, probably because it seems to have been an exhibition catalogue.
The site that made this possible is new to me, and seems to be an official “Italian digital internet” site:
I searched on “mitreo” and there it was.
I’m not entirely clear what the remit of the site is. But nevertheless, it seems to contain some very hard to find material!
UPDATE: Oh good grief … the PDF contains … only the cover and its reverse. No content whatever! Drat.