《汉书·志·地理志上》
比苏县，贲古县，北面采山出产锡，西面羊山出产银和铅，南面乌山出产锡。
比苏，贲古，北采山出锡，西羊人出银、铅，南乌山出锡。
Bisu County: Penghu County: Tin is produced from the mountains in the north, silver and lead are produced from Yangshan Mountain in the west, and tin is produced from Wushan Mountain in the south.