Message

An item in a shopping cart MUST be uniquely identifiable by either "item sellers identifier" or "item standard identifier"

Context
//cac:Item
Test
(cac:SellersItemIdentification) or (cac:StandardItemIdentification)
Usage
/ ubl:Catalogue / cac:CatalogueLine / cac:Item / cac:SellersItemIdentification / cbc:ID
/ ubl:Catalogue / cac:CatalogueLine / cac:Item / cac:StandardItemIdentification / cbc:ID