Yes, you need to have the List of internal documents. The purpose of this list is to catalogize all documents that have been created for the management system. It doesn't matter if they are in electronic or paper form. This list tells you which documents are currently in use, which version of that document is currently active, and since when.
External documents are all documents that come into your company and are necessary for your work. This usually includes laws and regulations, contracts with suppliers and customers, and similar.
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