Within the Mongol Empire, which eventually included all of China, there were enough Westerners travelling there that in 1340 AD Francesco Balducci Pegolotti compiled a guide book for fellow merchants on how to exchange silver for paper money to purchase silk in Khanbaliq (Beijing). By this stage the Eastern Roman Empire, temporarily dismantled by the Latin Empire, had shrunk to the size of a rump state in parts of Greece and Anatolia. Ma Duanlin, author of the "Wenxian Tongkao", noted the shifting political boundaries, albeit based on generally inaccurate and distorted political geography. He wrote that historians of the Tang Dynasty considered "Daqin" and "Fulin" to be the same country, but he had his reservations about this due to discrepancies in geographical accounts and other concerns (Wade–Giles spelling):