信用证有一条款如下:INSURANCE COVERED BY THE OPENERS ALL SHIPMENT UNDER THIS CREDIT MUST BE ADVISED BY THE BENEFICARY WITHIN 3 WORKING DAYS OF SHIPMENT TO *** GEBERAL INSURANCE COMPANY LID AND TO THE OPENER REFERERRING TO COVER NOTE NO.** GIVING FULL DEAILS OF SHIPMENT COPIES SUCH SHIPMENT ADVICES TO ACCOPANY THE ORIGINAL DOCUMENTS.
麻烦各位帮忙解释,是要怎么做单证?