1. Philatelic 72/22/1/66 Reference (shelfmark): Philatelic 72/22/1/66 Title: The People's Republic of China Mini-Sheet Issue: National Science Conference Scope & Content: Stamps designed by Xu Yanbo. Manufactured by the Beijing Postage Stamp Printing Works using a photogravure printing process. Collection Area: Philatelic Collections Languages: English Date Range: 18 Mar 1978 Extent: 3 Items