Problem with foreign key between 3 tables. (PgAdminIII)
It would have been good if you provided the foreign keys that failed. The following should work:

ALTER TABLE public."OrarioToLocale"
    ADD CONSTRAINT FK_... FOREIGN KEY ("IDorarioT")
        REFERENCES public."Orario" ("IDorario");


and a similar constraint for Locale. Why do the attributes in OrarioToLocale end with a T?