What is the flexfield code for the "Preferred Electronic Invoice Delivery Method"?

Summary:

I am attempting to set up the Transaction Printing After Electronic Invoice Generation from 24C and this is one of the steps but the code name and module are not listed in the configuration steps.

Steps to enable are below: - I am specifically asking about step 3:

To enable the Print Receivables transactions after Electronic Invoice generation feature for Legal Entity, follow these steps to define the Preferred Electronic Invoice Delivery Method descriptive flexfield:

1. Navigate to the Setup and Maintenance > Legal Structures > Manage Legal Entity Financial Information task.
2. Search for the Legal Entity you want.
3. In the Preferred Electronic Invoice Delivery Method descriptive flexfield, define the value XML delivery along with PDF generation.