Context diagram questions


Hi.
I'm analysing a new system that would:
1. Convert existing data (Excel + Magic) into the new system
2. Scan documents into the new system
3. Get documents by Fax, into the new system
4. Export data to an external system.

As to the context diagram, using the same numbers:
1. Conversion. Would this be "inside" the system?
Or would a user (running the conversion application) enter the data
from Excel etc. From the outside into the system?
2. How should I draw this? "Scan team" external entity entering
"Scanned docs" into the system?
3. Same question for the fax.
4. Would the external system be an "External entity" getting output
from the system?
TIA

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