https://help.myob.com/wiki/x/8h_EAQ
You can link an external document to a period where the document doesn't relate to a specific account.
Linking an external document to an account
Linking to references in external documents
Adding workpapers
Viewing a list of all workpapers and source documents
Opening workpapers
Opening source documents
Deleting workpapers and source documents
Importing the client's balances
Adding journals
Opening an existing period
Opening Document Manager files