Accompanying letter of the foreign office for 2 covers, which was the 2. Return journey of the" U-GERMANY with diplomatic post were transported and to the" Vienna bank association" arranged are. Censorship release and seal of office" German Reich foreign office", as well reference" about without prepaid postage dispatch ( registered mail) the here expertized 2 covers becomes asked". The accompanying letter with the both covers is to the Imperial Message in Vienna arranged, the covers were there the post office Vienna 8 hand over and the accompanying letter is carrying arrival mark" at the 30. August 1916 in Vienna arrived". Extremely rare document and the most meaningful ever. Us is only another copy known. Connoisseurs piece!