1937 and 1939 a pair of Siamese 15 stg stationery covers from Bangkok to Swatow, applied with Bangkok rice-selling promotional d.s. Showing
1937 and 1939 a pair of Siamese 15 stg stationery covers from Bangkok to Swatow, applied with Bangkok rice-selling promotional d.s. Showing vertical Qiaopiju vertical cachet and number1937及1939年一對暹羅15士打郵資封，自曼谷寄汕頭，銷曼谷大米宣傳機戳。另見批局直戳及編號。
