英语翻译求救,请大家帮看看 A documentary collection can be defined as the

英语翻译
求救,请大家帮看看 A documentary collection can be defined as the collection of a sum due from a buyer by a bank actiong on behalf of a seller against delivery of certain documents.怎么译.documentary collection 是跟单托收的意思.
我的意思是想从这段话的意思来分析.一楼说的根本和这句话没什么联系呀!