《明史·列传·卷一百二十九》
过去的惯例，让商人承办内府的器物，都要签名然后送进去，叫作佥商。
故事，令商人办内府器物，佥名以进，谓之佥商。
In the past, merchants who handled the emperor's personal belongings had to sign their names on them before sending them in; this was called "Qian-shang."