cover 1931 (12 Nov.) Chinese money envelope to Harbin bearing 1931 Ulan Bator provisional 1c. pair and 20c. tied by double-ring Ulan Bator c.d.s., China 30c. postage due tied by Harbin bilingual c.d.s. alongside; the envelope has been opened out for display, some glue stains, still fine and appealing