Mushrooms, Myth & Mithras: The Drug Cult that Civilized Europe
Carl Ruck, Mark Alwin Hoffman, José Alfredo González Celdrán (on Google Books)
Mithraic findings in cave in Austria in St. Egyden. Vessel with Serpents, ineresting and beautiful piece, look at:
IN GERMAN: Heidnischer Kult in Höhle entdeckt