How to close period without creating accountings for some invoices in AP?

 Hi:Can you guide me about a problem in Payables with SLA.

I'm uploading historic invoices as an initial data setup. Those transactions are for reference purposes only, so would not like to create accounting entries for that transactions in SLA.

The way I tried to accomplish this issue, is under the SLA, at the application account definition for payables invoices, the flag "Create Accounting" is disabled (unchecked).

When I create accounting for the transaction (invoice), the application shows succesfull message, and no accounting is generated in the SLA. Until here fine.

The problem is that the period cannot be closed because the system requires every document to be posted, but how can I account for a document without creating acounting entries in SLA?