《史记·三十世家·绛侯周勃世家》
周勃被封赐列侯的爵位，高祖分剖符信保证周勃的爵位代代相传，永不断绝。
赐爵列侯，剖符世世勿绝。
Zhou Bo was enfeoffed as a marquess. Gaozu divided the talisman to guarantee that his title would be passed down from generation to generation, without interruption.