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The Planning Document field is available if the Use a payment calendar option is selected on the Administration > Settings > Cash Management Money form. The field is auto- populated in case of the cash receipt based on a Money Transfer (Plan) or Money Receipt (Plan) document.
If the Project Costing functionality is enabled in the application on the Administration > Settings > General Settings form Project Costing form, you can link the cash receipt with a related project which you can select in the Project field (to find a project, start typing its name or code in the field).
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