cover 10pa. orange (6, three horizontal pairs) affixed to 1880 (1 Nov.) envelope registered to Austria (3.11 arrival backstamp), all cancelled by "BEOGRAD" c.d.s. and showing framed "RECOMM" h.s. adjacent; the envelope is lightly soiled and with small peripheral tears. Used one day after the validity of the Prince Milan issue. A most interesting piece. M.12V. Photo