英语：“付款方式：月结30天付款”，应该怎么写？

“月结30天”，这是一个表述两可的概念。
按照通常的理解
月结30天:就是本月所有发的货在月底对帐结算,再过30天付款.
如果按照上述说法翻译, 我认为:
Payment terms: credit time :30days 或者 Settlement time: 30 days

如果楼主意思是发货后30天内付款，那么翻译成
The paymment will be effected within 30 days after (the date of) delivery

For payment of your invoice, I believe you have no objection to delivery of documents against acceptance on 30 days draft?
对于贵发票的付款方式，以承兑交单三十天付款，我想你大概没异议吧？

We propose to pay by Bill of Exchange at 30 d/s, documents agaist acceptance.
我们建议以见票30天付款的汇票承兑交单方式付款。

Payment method: monthly payment in 30 days
付款方式：月结30天付款

Payment terms: pay on a monthly basis within 30 days.

paid within 30 days