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In the Entity field, select an entity of your company for which this document is being prepared. The Entity field is available if the Multi-Company Accounting option is selected on the following form: Administration > Settings> General Settings. You can select your personal default entity to appear in documents that you create; for this, refer to Personal Settings. If If you have not selected your default entity, the entity defined first will be used as the system default value.
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For descriptions of other buttons, see Document Toolbar.
Use the Settings button to invoke the Document Settings dialog box if you need to move the Project field from the document header (the Main tab) as a column to the table on the Payment Details tab or back.
The Document Settings dialog box
Once you are done with the option selection, click OK to save the settings and close the dialog box or Cancel to close the dialog box without any changes to the settings.